How many times does the digit 7 appear from 1 to 100?

How many times does the digit 7 appear from 1 to 100?

Explanation

Digit 7 appears in both units and tens places.

Total count = 9 (units) + 9 (tens) + 1 (double 7 in 77)

= 19 + 1

= 20 times.