What is the average of all numbers between 8 and 74 which are divisible by 7?

I am not sure, may be 41 is correct

No.of terms= (last term-first term)/d -1
=(70-14)/7 -1
=9
Sum=n/2 (last term +first term)
9/2 (84)
Avg=(9×84)/(2×9)
=42

All the numbers between 8 & 74 which are divisible by 7 is...

1st = 14

last = 70

Average:- (1st number+last number)/2

=(14+70)/2

=84/2

= 42

sum of n terms is n/2(2a+(n-1)d) .............(formula)

n is number of terms

a is first term

d is difference between first two cosecutive numbers

numbers between 8 to 74 which is divisible by 7 is 7 table

sequence is 14 21 28 35 42 49 56 63 70

now apply formula n is 9 terms

a is 14 and d is 7

sum of terms is 9/2(2(14)+(8)7) =4.5(84) =378

average is 378/9 =42