Question

Find the sum of 3+33+333+...upto n terms of an Ap

Answer 1

Answer:

This example has up to 12 terms available .

Step-by-step explanation:

The question is 3+33+333+…..12 terms. We can write it as

3(1+11+111+….12 terms)

=(3/9)(9+99+999+….12 terms)

=(3/9)((10 - 1) + (100 - 1) + (1000 -1)…12 terms) we can use the geometric series summation here.

=(3/9)(10)(10^12 - 1)/9) - (3/9)(12)

=(10(10^12–1)/27) - 4

=(9999999999990/27) - 4 = 370,370,370,366