Question

Find the sum of the digits of the number 6+66+666+6666 + ... +666...66, where the last number contains 100 digits.

Answer 1

Answer:

30300

Step-by-step explanation:

Actually, se have an arithmetic progression:

6, 12, 18, 24... 600

$S = \frac{(6 + 600).100}{2} \\\\ S = (6 + 600).50 \\\ S = 300 + 30000 \\\ S = 30300$

I hope I've helped you.