Question

The average of ten numbers is 34. If the average of the first four numbers is 24 and the average of the next four numbers is 37.75 and the value of the 10th number is one more than the value of the 9th number, then find the value of the 10th number.

• A. 46
• B. 40
• C. 44
• D. 47

Answer 1

Answer:

D. 47

The sum of ten numbers = 34 × 10 = 340 The sum of the first four numbers = 24 × 4 = 96 The sum of the next four numbers = 37.75 × 4 = 151 The sum of first eight number = 96 + 151 = 247 The sum of 9th and 10th number = 340 - 247 = 93 Let the value of 9th number is x. The value of 10th number = x + 1 x + x + 1 = 93 2x + 1 = 93 2x = 92 x = 46 value of 10th number = 46 + 1 = 47