What is the average of all whole numbers between 50 and 200 that are divisible by 7?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 126.
First term: 56, last term: 196
Sequence: 56, 63, …, 196
Common difference 7
Number of terms: [(196 − 56)/7] + 1 = 140/7 + 1 = 20 + 1 = 21 terms
Average = (first + last)/2 = (56 + 196)/2 = 252/2 = 126