Question

Find the sum of all number between 100 and 200 which is divisible by 2 and 5

Answer 1

Answer:

Numbers between 100 and 200 divisible by 2 and 5 are:-

110 , 120 , 130 , 140 , 150 , 160 , 170 , 180 , 190

Clearly, a = 110 , n = 9 , l = 190

Therefore

Sn = n / 2 (a + l)

= 9 / 2 (110 + 190)

= 9 / 2 × 300

= 1350

:) Thanks!