Question

(C) Find the sum of all odd integer
between 2 and 100 divisible by 3.
CBSE 2013​

Answer 1

Answer:

867

ANSWER

The odd integers between 2 and 100 which are divisible by 3 are 3, 9, 15, 21, ..., 99.

Here, a=3 and d=6.

a

n

=99

⇒a+(n−1)d=99

⇒3+(n−1)×6=99

⇒6(n−1)=96

⇒n−1=16

⇒n=17

Therefore,

Required sum =

2

n

(a+l)=

2

17

(3+99)=867