#math trivia #79 solution

Burt Kaliski Jr. (@modulomathy)
3/19/12 10:37 PM
#math trivia for #March19: #79 has one of the highest digit sums of any two-digit prime: 7+9=16. Which two-digit prime has a higher sum?

The only two-digit prime with a higher digit sum than 79 is 89.

Indeed, the only two-digit numbers with a higher digit sum than 79 are 89, 98, and 99, and only the first of the three is a prime.

Which three-digit prime has the highest digit sum?

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