Question

The average of 5 numbers is 65. The average of the first two numbers is 81 and the average of the last two numbers is 38. What is the third number?
(1) 63
(2) 87
(3) 99
(4) Cannot be determined
(5) None of these

Answer 1

87.
the total for 5 numbers = 65x5=325
total for first two numbers=81x2=162
total for last two numbers=38x2=76
hence third number = 325-(162+76)=87

Answer 2

Answer:

87

Step-by-step explanation:

Total of Five No: 5x65= 325.

and now assume 3rd number is y;

hence,

(2x81)+y+(2x38) = 325,

162+y+76 = 325,

y+238 = 325,

y=325-238,

y= 87

Hence 3rd number is 87,