Preperation of Mental Arithmetic



Question No 1

Multiply 7 by 4 by 6.

Select the correct answer


Solution!
7 * 4 = 28! !28 * 6 = 168.

Question No 2

What is 9 multiplied by 8?

Select the correct answer


Solution!
9 * 8 = 72.

Question No 3

What is 5.9 + 6.8 + 7.34?

Select the correct answer


Solution!
6.8 + 7.34 = 14.14! !14.14 + 5.9 = 20.04.

Question No 4

The side of a square is 2. What is the area of the square?

Select the correct answer


Solution!
Area of square is!2 * (any side)!= 2 * (2) = 4 square units.

Question No 5

Deduct 865 from 1063.

Select the correct answer


Solution!
1063 - 865 = 198.

Question No 6

Divide 52 by 4 and add 17 multiplied by 3.

Select the correct answer


Solution!
52 / 4 = 13! !17 * 3 = 51! !13 + 51 = 64.

Question No 7

Divide 56 by 8 and add 17.

Select the correct answer


Solution!
56 / 8 = 7! !7 + 17 = 24.

Question No 8

What is average of 3, 5 and 10?

Select the correct answer


Solution!
(3+5+10)/3 = 18/3 = 6.

Question No 9

Add 32 + 8 + 18 + 25.

Select the correct answer


Solution!
32 + 8 = 40! !40 + 18 = 58! !58 + 25 = 83.

Question No 10

What is 8/40 expressed as a decimal?

Select the correct answer


Solution!
Simple way is! !(8/4) * (1/10) = 2 * 0.1 = 0.2.

Question No 11

15 weavers can weave some length of cloth in 1 hr. 24 minutes. How many more weavers are required to do the same job in 60 minutes?

Select the correct answer


Solution!
x/15 = 84/60! !x = (84/60)*15 = 21! !So 21 - 15 = 6 more weavers are required to do the same job in 60 minutes..

Question No 12

What is 55% of 320?

Select the correct answer


Solution!
55 * (320 / 100) = 176! !Quick way to find answer from options is! !50% of 320 is 160 so answer should be greater than 160!Only one option is greater than 160 which is 176..

Question No 13

Divide 672 by 12.

Select the correct answer


Solution!
672 / 12 = 56.

Question No 14

What must be added to each numerator and denominator of 13/29 so that it becomes 1/2

Select the correct answer


Solution!
(13+3)/(29+3) = 1/2.

Question No 15

What is the sum of first 5 positive even integers?

Select the correct answer


Solution!
2+4+6+8+10 = 30.

Question No 16

What is the average of 8, 13, 25, 43, and 11?

Select the correct answer


Solution!
(8+13+25+43+11)/5 = 100/5!= 20.

Question No 17

If x = 8*89 and y = 8*85, What is the value of x-y ?

Select the correct answer


Solution!
(8*89) - (8*85)!=8*(89 - 85)!=8*(4)=!32.

Question No 18

Which one of the following is a prime number ?

Select the correct answer


Solution!
307 is only number which is divisible by 1 and by itself only..

Question No 19

100/101 = ?

Select the correct answer


Solution!
100/101 = 0.990099.

Question No 20

What is average of 2 , 5 and 8?

Select the correct answer


Solution!
(2+5+8)/3 = 15/3 = 5.

Question No 21

If the sum of three consecutive whole numbers is 15, what is the largest of the three numbers?

Select the correct answer


Solution!
6+5+4 = 15.

Question No 22

Ahmad reads 24 pages of a book in 15 minutes. The rate of pages read per minute by him will be

Select the correct answer


Solution!
24/15 = 8/5!8/5 = 1.6.

Question No 23

Multiply 15 by 6 and subtract 29.

Select the correct answer


Solution!
15 * 6 = 90! !90 - 29 = 61.

Question No 24

49/10 + 49/10 + 49/10 = ?

Select the correct answer


Solution!
By taking LCM of these three terms we have! !(49+49+49)/10 = 147/10.

Question No 25

What is 15 multiplied by 11?

Select the correct answer


Solution!
15 * 11 = 165.

Question No 26

Average of 4 numbers is 24. What is the sum of the four numbers?

Select the correct answer


Solution!
x/4 = 24!x = 24*4!x = 96.

Question No 27

If m is an even integer and 3m < 48 and 2m > 24 then m = ?

Select the correct answer


Solution!
3*14 = 42 (lesser than 48)!and!2*14 = 28 (greater than 24)..

Question No 28

Multiply 6.85 by 7.

Select the correct answer


Solution!
6.85 * 7 = 47.95.

Question No 29

A cigarette case is full of cigars and cigarettes, probability of a cigarette is 8/15. What is the ratio of cigars to cigarettes.

Select the correct answer


Solution!
In 15 cigars and cigarettes there are 8 cigarettes So ratio between cigars and cigarettes is 8/7. Which means there are 8 cigarettes and 7 cigars..

Question No 30

What is the difference of the product and the quotient of 8 and 8?

Select the correct answer


Solution!
8*8 = 64!and!8/8 = 1!So,!64 - 1 = 63.

Question No 31

If one third of the staff at school are teachers find the ratio between teachers to non-teachers.

Select the correct answer


Solution!
ratio of teachers = 1/3! !ratio of non-teachers = 2/3! !Ratio of teachers to non-teachers = (1/3) * (3/2) = 1/2.

Question No 32

John's fail to pass ratio in mathematics test is 5/2. In how many tests did he pass if total tests conducted were 42?

Select the correct answer


Solution!
Pass ratio = (2/7)*42 = 12.

Question No 33

A motorcyclist travels 200 Km in 1 hr. How many minutes if would take him to travel 120 Km?

Select the correct answer


Solution!
200 Km distance covered in minutes = 60! !1 Km distance covered in minutes = 60/200 = 3/10! !120 Km distance covered in minutes = (3/10) * 120 = 36 minutes.

Question No 34

If average of 8, 7, 12, 15 and x is 11 what is x?

Select the correct answer


Solution!
(8+7+12+15+x)/5 = 11! !42+x = 55! !x = 55-42!=13.

Question No 35

64% of the children in school are girls.What percentage are boys?

Select the correct answer


Solution!
100 - 64 = 36%.

Question No 36

What is smallest integer greater than 1 that leaves remainder 1 when it is divided by 5 or 8?

Select the correct answer


Solution!
40 is the least common multiple of 5 and 8 so 41 will be the smalles integer that leaves 1 when it is divided by 5 or 8..

Question No 37

Subtract eight and nine from twenty-five.

Select the correct answer


Solution!
25 - 8 - 9 = 8.

Question No 38

16 men dig a ditch in 10 days. How many men would be required to complete the job in half the time?

Select the correct answer


Solution!
Double number of men are required to complete the job in half time..

Question No 39

John can read 8 pages of a book in 7 minutes, how long will he take to read 40 pages?

Select the correct answer


Solution!
40/8 = 5! !As pages are increased 5 times. So minutes will also increase 5 time.! !7 * 5 = 35.

Question No 40

At a particular time shadow of a pole 40m long is measured to be 30m. If the length of a plaza is 200m then how long would the shadow be at about the same time?

Select the correct answer


Solution!
Shadow of 40m pole = 30m! !Shadow of 1m pole = 30/40m! !Shadow of 200m plaza = (30/40)*200 = 150m.

Question No 41

When R is divided by 7 remainder is 3. What is the remainder when 3R is divided by 7?

Select the correct answer


Solution!
No answer description is available for this question..

Question No 42

If A/B is 2/3 and difference between values of A and B is 10 What is value of B?

Select the correct answer


Solution!
If B is 30, A is 20 so difference of 10 is maintained..

Question No 43

If n is not equal to 0, Which of the following must be greater than n? (1) 2n (2) n^2 (3) 2-n

Select the correct answer


Solution!
Square of every non zero integer is grater than the orignal number.! !*Note that multiple of 2 of negative numbers are lesser than the orignal number..

Question No 44

In a class the ratio of boys to girls is 1/3. What percent of students are girls?

Select the correct answer


Solution!
Percentage of girls in class = (3/4)*100 = 75%.

Question No 45

What is 5/9 of 270?

Select the correct answer


Solution!
(5/9) * 270 = 150.

Question No 46

Which is greater, (A) 5/8 of 112 , (B) 7/8 of 88?

Select the correct answer


Solution!
(5/8) * 112 = 70! !and!(7/8) * 88 = 77! !Hence, (7/8) of 88 is greater..

Question No 47

The average of 20 numbers is 0, How many of them may be greater than zero,at the most?

Select the correct answer


Solution!
Maximum Numbers that can be greater than 0 to maintain total average greater than 0 are 19..

Question No 48

In the first 10 overs of a cricket game the run rate was only 3.2 What should be the run rate in the remaining 40 overs to reach the target of 282?

Select the correct answer


Solution!
3.2 * 10 = 32! !After 10 overs score is 32.! !Remaining score = 282 - 32 = 250! !Required rate = 250 / 40 = 6.25 runs/over.

Question No 49

What is the largest 4 digit number exactly divisible by 88?

Select the correct answer


Solution!
No answer description available for this question..

Question No 50

A/B = 2/3. If value of A is 8 What is the value of B?

Select the correct answer


Solution!
8/B = 2/3!2B = 24!B = 12! !*In short-cut way We can find 2 is multiplied by 4 to get 8 so if we multiply 3 with 4 we get 12 which is the value b B when value of A is 8..

Question No 51

35 Kg of spinach costs Rs. 28. How many Kg of spinach can be bought for Rs. 16?

Select the correct answer


Solution!
Amount of spinach which can be bought in Rs. 28 = 35 kg! !Amount of spinach which can be bought in Rs. 1 = 35/28 = 5/4 Kg! !Amount of spinach which can be bought in Rs. 16 =(5/4)*16 = 20 Kg.

Question No 52

Add 2/5 of 90 to 5/6 of 78.

Select the correct answer


Solution!
(2/5) * 90 = 36! !(5/6) * 78 = 65! !36 + 65 = 101.

Question No 53

What is average of 2, 5 , 6 , 9 and 18?

Select the correct answer


Solution!
(2+5+6+9+18)/5 = 40/5 = 8.

Question No 54

Multiply 72 by 15.

Select the correct answer


Solution!
72 * 15 = 1080! !Other way is! !72 * 10 = 720!and!720 / 2 = 360! !720 + 360 = 1080.

Question No 55

Which of the following is an integer that has a remainder of 1 when it is divided by 4,5 and 6?

Select the correct answer


Solution!
Least common multiple of 4,5 and 6 is 60 so 61 is an integer that has a remainder of 1 when it is divided by 4,5 and 6..

Question No 56

Deduct 7.3 from 34.2.

Select the correct answer


Solution!
34.2 - 7.3 = 26.9.

Question No 57

At an educational trip of a school ratio of boys to girls students was 4/5. how many students were on the tour?

Select the correct answer


Solution!
Data is insufficient for this problem. But we can find the answer from the options. As 4 + 5 = 9, So answer should be multiple of 9 to fullfil the condition of 4/5 ratio..

Question No 58

2+2*2?

Select the correct answer


Solution!
2 + (2 * 2) = 6! !Multiplication is performed first and subtraction afterwards.! !Sequence of solving operators is!/!*!+!-.

Question No 59

If the number 481z673 is completely divisible by 9, what is the the smallest whole number in place of z?

Select the correct answer


Solution!
Select answer from options! !4817673 is completely devisible by 9..

Question No 60

A bus covers a distance of 60 Km in 1.5 hr. How far it would travel in half hour.

Select the correct answer


Solution!
Distance covered in 1.5 hr = 60! !Distance covered in 1 hr = 60/1.5 = 40 Km! !Distance Covered in 0.5 hr = 40 * 0.5 = 20.

Question No 61

In a Zoo deers and lions are in ratio of 5/2. If there are 20 deers how many lion are there?

Select the correct answer


Solution!
20 is 4 times of 5 So in this way 4 times of 2 will be 8..

Question No 62

Subtract 369 from 1250.

Select the correct answer


Solution!
1250 - 369 = 881.

Question No 63

What is 3/4 of 92 plus 13?

Select the correct answer


Solution!
(3/4) * 92 = 69! !69 + 13 = 82.

Question No 64

Multiply 86 by 9 and add to 13 multiplied by 6.

Select the correct answer


Solution!
86 * 9 = 774! !13 * 6 = 78! !774 + 78 = 852.

Question No 65

The average weight of 16 boys in a class is 50.25 kg and that of the remaining 8 boys is 45.15 kg.Find the average weights of all the boys in the class.

Select the correct answer


Solution!
! !In this question weighted average is calculated rather than simple average! !(50.25*16 + 45.15*8)/(16+8) = 48.55.

Question No 66

What is 126 divided by 3?

Select the correct answer


Solution!
126 / 3 = 42.

Question No 67

Multiply 7 by 12 and divide by 6.

Select the correct answer


Solution!
7 * 12 = 84! !84 / 6 = 14.

Question No 68

What is 5/8 of 240?

Select the correct answer


Solution!
(5/8) * 240 = 150.

Question No 69

Multiply 694 by 11.

Select the correct answer


Solution!
694 * 11 = 7634! !Quick way to find answer from options is! !694 * 10 = 6940! !So answer must be greater than 6940 and only one option is greater than 6940 which is 7634..

Question No 70

What is 10 less 5/9 of 117?

Select the correct answer


Solution!
(5/9) * 117 = 65! !65 - 10 = 55.

Question No 71

378 * ? = 252

Select the correct answer


Solution!
252 / 378 = 2/3.

Question No 72

What is average of 12 , 15 and 18?

Select the correct answer


Solution!
(12+15+18)/3 = 45/3 = 15.

Question No 73

If a amount of $120 is divided among A and B in the ratio 1/2 then A will get?

Select the correct answer


Solution!
A will get half amount which B got.So if A's amount is 40, B's amount will be 80 (double of A's amount)..

Question No 74

If the product of 4 consecutive integers is 120, which is greater?

Select the correct answer


Solution!
5*4*3*2 = 120.

Question No 75

If the number 5r2 is divisible by 6, then r = ?

Select the correct answer


Solution!
572 is completely divisible by 6..

Question No 76

Which of the following is a prime number?

Select the correct answer


Solution!
A prime number is the number which is divisible by 1 and by itself only! !and 2 is the only one even number which is prime..

Question No 77

A coach trip starts at nine fifty.It lasts twenty-five minutes.At what time does it finish?

Select the correct answer


Solution!
No answer description available for this question..

Question No 78

If n is even, Which of the following cannot be odd? (1) n+3 (2) 3n (3) n^2 - 1

Select the correct answer


Solution!
3n and n^2 - 1 will always odd so in case of 3n answers will be even..

Question No 79

15 men were hired to plough a piece of land in 10 days. How many more men will be required to do the same job in 3 days?

Select the correct answer


Solution!
x/15 = 10/3! !x = (10/3)*15! x = 50.! !So more number of men required = 50-15 = 35.

Question No 80

30 men can complete a work in 30 days how long will 20 men take to complete the same amount of work?

Select the correct answer


Solution!
x/30 = 30/20! !x = (30/20)*30 = 45.

Question No 81

What is 35% of 250?

Select the correct answer


Solution!
35 * (250/100) = 87.5! !Quick way to find answer from options is! !33% of 250 is nearly 83(250/3 = 83.3)! !So, answer should be in 80's which is only one option 87.5.

Question No 82

Price of a mobile phone is Rs. 8,000. A man has enough money to purchase 3 mobiles. How many mobile can he purchase if the price is reduced by Rs. 2000?

Select the correct answer


Solution!
Minimum amount of money that he has = 8,000 * 3 = 24,000! !If price is reduced to 6,000, he can purchase 24,000/6,000 = 4.

Question No 83

Ali can type at a speed of 25 words per minute. How many words he can type in one hour?

Select the correct answer


Solution!
Typed words in 1 minute = 25!Typed words in 60 minutes = 60 * 25 = 1500.

Question No 84

What is the cost of three tapes at $1.99 each?

Select the correct answer


Solution!
1.99 * 3 = $5.97.

Question No 85

If p is and odd integer and 7p > 50 and 3p < 35 then p is?

Select the correct answer


Solution!
7*11 = 77 (greater than 35) and 3*7 = 33 (lesser than 35)! !*Note that 8 is also true but in question it is explicitly said that integer must be odd..

Question No 86

A number is thrift if it is a multiple of 2 or 3. How many thrift numbers are there between 0 and 15?

Select the correct answer


Solution!
Thrift numbers between 0 and 15 are following! !2,3,4,6,8,9,10,12,14.

Question No 87

Which of the following is the least number which is divisible by both 12 and 18?

Select the correct answer


Solution!
Least common multiple of 12 and 18 is 36.

Question No 88

Which of the following fractions is closed to 0.5?

Select the correct answer


Solution!
15/30 = 1/2!1/2 = 0.5.

Question No 89

A cycle costs $170.Jane saves $50 each week.How many weeks will it be before she can buy it?

Select the correct answer


Solution!
170 / 50 = 3.4!But 3.4 is not in options so nearest Option is 4.

Question No 90

If the average marks of three batches of 55, 60 and 45 students respectively is 50, 55, 60, what is the average marks of all the students?

Select the correct answer


Solution!
Weighted average will be more close to the average of that batch which has maximum number of students so aanswer is 54.68! !If you want to calculate it by formula then solution is! !(55*50 + 60*55 + 45*60)/(55 + 60 + 45) = 54.68.

Question No 91

In a box ratio of DVD to VCD is 2/3. Which of the following cannot be the total number of CD's in the box?

Select the correct answer


Solution!
As 2+3 = 5, So total number of CD's must be multiple of 5.! !In the options all are multiple of 5 except 11! !So 11 is the correct answer..

Question No 92

What is 45% of 300?

Select the correct answer


Solution!
45 * (300/100) = 135! !Quick way to find answer from options is! !50% of 300 is 150 so 45% of 300 should be less than 150! !So, it may be 149 or 135!149 is very close to 150 which is not possible! !Hence, 135 is correct answer..

Question No 93

Average of 3 numbers is 15. What is the sum of 3 numbers?

Select the correct answer


Solution!
Let sum is x. ! !x/3 = 15!x = 15*3 = 45.

Question No 94

What is 3206 divided by 7?

Select the correct answer


Solution!
3206 / 7 = 458! !No need to perform complete devision first digit comes 4 after devision and there is only one option in which first digit is 4..

Question No 95

How much is 25% of $200?

Select the correct answer


Solution!
25 * (200/100) = $50! !Or!200 / 4 = $50.

Question No 96

2664/12/6=?

Select the correct answer


Solution!
(2664/12) * (1/6) = 37.

Question No 97

Sum of three consecutive odd integers is 51. Which of the following is the smallest of the three?

Select the correct answer


Solution!
19+17+15 = 51.

Question No 98

7/21 in lowest term is?

Select the correct answer


Solution!
7/21 = 1/3.

Question No 99

The average of five numbers is 27.If one number is excluded the average becomes 25.What is the excluded number?

Select the correct answer


Solution!
No answer description available for this question..

Question No 100

Add 5683 to 1729 and divide by 2.

Select the correct answer


Solution!
5683 + 1729 = 7412! !7412 / 2 = 3706.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100

IQTestprepration@2018 All Rights Reserved