Question

Rosa likes to calculate the sum of the digits she sees on her digital clock (for example, if the clock says 21:17, Rosa gets 11). What is the maximum amount that can be obtained?

Answer 1

19

Explanation:

The maximum amount of the sum of digits that can be obtained from a digital clock is 27.

To see why, note that the maximum value for the hour digits is 23 (since the clock uses a 24-hour format). The sum of digits in 23 is 2+3=5.

For the minute digits, the maximum value is 59. The sum of digits in 59 is 5+9=14.

Adding the two sums of digits together, we get:

5 + 14 = 19

Therefore, 19 is the maximum sum of digits that can be obtained from the hour and minute digits on a digital clock