Question

The average of 15 results is 40 and that of first seven is 30 and that of last seven is 34. The value of 8th result is:

• A. 160
• B. 152
• C. 138
• D. 148
• E. 158

Answer 1

The correct option is B

152

8${}^{th}$ number will be = Sum of 15 results - (Sum of first seven + Sum of last seven) = (15 x 40) - (7 x 30 + 7 x 34) = 152.