Inspector Investigation FIA Past Paper- Page 7 of 10

The average age of 3 friends is 23. Even if the age of the 4th is added the average remains 23. what is the age of 4th friend?

A) 21 yrs

B) 23 yrs

C) 32 yrs

D) None of these

Sum of the ages of 3 friends $= 3 \times 23 = 69 y e a r s$
Sum of the ages of 4 friends $= 4 \times 23 = 92 y e a r s$
$∴$ Age of 4th friend = 92 years – 69 years = 23 years

The average of 6 numbers is 30. If the Average of first four is 25 and that of last three 35. What is the fourth number?

A) 25

B) 30

C) 35

D) None of these

six numbers are: a,b,c,d,e,f
Then
a+b+c+d = 25×4 = 100
d+e+f = 35×3 = 105
a+b+c+d+e+f = 30×6 = 180
then the fourth number is:
d=100+105-180=25

The average of the numbers 15, 5, 0,12, 8 is?

A) 8

B) 8.5

C) 10

D) None of these

Which number must be added to 2203 to get a perfect square?

A) 1

B) 3

C) 5

D) None of these

√31684 = ?

A) 108

B) 172

C) 5

D) 178

If √4n² = 24 then the value of n is?

A) 4

B) 6

C) 5

D) None of these

√10× √250= ?

A) 46.95

B) 43.75

C) 50

D) None of these

√0.4= ?

A) 0.2

B) 0.02

C) 0.632

D) None of these

6250/√?= 625

A) 10

B) 95

C) 100

D) None of these

The difference of 1 integer 3/16 and its reciprocal is?

A) 1 1/8

B) 1 1/3

C) 15/16

D) None of these

Required difference = 19/16−16/19

by solving we get:

=105/304