AFCAT Model Paper 2

Formula used:
Sum of an arithmetic progression(S) =(

n

2

)[2a+(n−1)d]
a = first term
n = number of terms
d = common difference
Average of n numbers = Sum of all numbers/n
Calculation:
a = 2; d = 2; n = 40
S=(

40

2

)[2×2+39×2]
⇒ S=40×41
∴ Required average =

(40×41)

40

=41