Question

Sum of three digit no. Wich multiples of 11

Answer 1

Answer:

it will form an AP

like

110, 121.........990

an = l = a + (n-1)(d) = 990

110 + (n-1)(11) = 990

n - 1 = 80

n = 79

S79 = 79/2 x (2a + (n-1)(d))

= 79/2 x (220 + 78(11))

S79 = 42581

Sum of three digit no. Which are multiples of 11

is 42581.

hope this will help you