[PSSSB JE, 2024]
2. If the average of 35 consecutive even numbers is 44. Find the sum of first and last numbers.
70
79
88
78
Correct Answer :
88
Given that the average of 35 consecutive even numbers is 44, we need to find the sum of the first and last numbers.
Let the first number be x and the last number be x+68 (since the difference between each consecutive even number is 2, and there are 34 steps between the first and last numbers).
The average of these numbers is given by:
\(Average = {\text{Sum of first and last numbers} \over 2}\)
Given that the average is 44:
\(44 = {x + x + 68 \over 2}\)
Simplifying:
\(44 = {2x + 68 \over 2}\)
\(44 = x + 34\)
Solving for x:
x = 44 − 34 = 10
Thus, the first number is 10 and the last number is 10 + 68 = 78
The sum of the first and last numbers is:
10 + 78 = 88