The ratio of two brothers John and Harry is 4 / 5. However if the age of John before 10 years and that of Harry after 10 years then the original ratio is reversed. What is the age of John?

John age is = a and harry= b

given that a /b = 5 / 4

4a= 5 b

4a - 5b= 0.... Equation 1

and also given that a - 10 / b + 10 = 4 / 5

5 a- 50 = 4 b + 40

5a - 4 b = 90.... Equation 2

by solving both equation

a = 50

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In following alphabet series , one term missing as shown by question mark . Choose missing term from options.

JE, LH, OL, SQ, ?

The first letter of the first, second, third,... terms are respectively moved two, three, four,... steps forward while the second letters of three terms are respectivvely moved three, four, five,... steps forward to obtain the corresponding letters of the successive terms..

A number was divided successively in order by 4, 5 and 6. The remainders were respectively 2, 3 and 4. The number is:

4 | x z = 6 x 1 + 4 = 10

5 | y -2 y = 5 x z + 3 = 5 x 10 + 3 = 53

6 | z - 3 x = 4 x y + 2 = 4 x 53 + 2 = 214

| 1 - 4

Hence, required number = 214.

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Excluding stoppages, the speed of train is 50 km per hour and including stoppages it is 40 km per hour. For how many minutes does the train stop per hour?

Due to stopages it is it covers 10 km less.

Time taken to cover 10 km= (10/50)*60 min = 12 min

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In following number series, two terms have been put within brackets. Choose the appropriate option

Choose the appropriate option 4, 7, (9), 10, 13, 15, (16), 19

Choose the appropriate option 4, 7, (9), 10, 13, 15, (16), 19

The correct sequence is is + 3, + 2, + 1, + 3, + 2, + 1, + 3.

Clearly, both the terms 9 and 16 are correct..