Answer: 12
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Work Shown:
5 digits = 1 second
50 digits = 10 seconds (multiply both sides by 10)
At the end of 10 seconds, he has written 50 digits.
The first 9 digits (1 through 9) are single digits. After writing them, Steve has 50-9 = 41 digits left.
41/2 = 20 remainder 1. So this means that he wrote 20 additional two-digit numbers after that 1 through 9 block of single digit numbers. Those two-digit numbers are 10 through 29. The last digit he writes is 3
So the last two digits he wrote was 9 and 3
Add them up get 9+3 = 12
