In the class of 10 boys and 5 girls boys have 4 balls each and girls have 1 ball each what will be the average number of balls in class?

={( number of boys X number of balls)+( number of girls X number of balls)}/ total students

={(10Ã—4)+(5Ã—1)}/10+5

=(40+5)/15

= 3 is the average number of balls in class.

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10 evacuator works 10 hour daily to remove 2500 cubic feet of Earth in 3 days. How many evacuator work 6 hour daily to remove 5000 cubic feet of Earth in 2 days?

Let x evacuator are required.

Evacuators are inversely proportional to hours and days are directly proportional to work progress

So,

X/10=(10/6)*(5000/2500)*(3/2)

=48

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If x and y are the two digits of the number 653xy such that this number is divisible by 80, then x + y = ?

80 = 2 x 5 x 8

Since 653xy is divisible by 2 and 5 both, so y = 0.

Now, 653x is divisible by 8, so 13x should be divisible by 8.

This happens when x = 6.

x + y = (6 + 0) = 6.

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

Z, L, X, J, V, H, T, F, ?, ?

The given sequence consists of two series -- Z, X, V, T, ? and L, J, H, F, ?, both consisting of alternate letters in a reverse order.

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Complete the Given Series

Which number replace question mark in the series 7, 12, 19, ?, 39.

Which number replace question mark in the series 7, 12, 19, ?, 39.

Clearly, the given sequence follows the pattern:

+5, +7, +9 ... i.e., 7 + 5 = 12, 12 + 7 = 19, ... .

So Missing Number = 19 + 9 = 28.

Hence, the answer is (B)..