Symbiosis National Aptitude Test SNAP 2019 Paper

Integers between 113 and 113113 which are divisible by 7 are 119, 126, 133, ..., 113113
This is an A.P. series with first term a = 119
Common difference d = 7
Last term b = 113113
Let n is the number of terms of this series, then form
b = (n – 1)d + a
113113 = 119 + (n – 1)7
(n - 1) =

113113−119

7

= 16142
∴ n = 16143
Sum of series of A.P.
=

n

2

[a+b]
=

16143

2

[119+113113]
= 913952088