The decimal number 61 is a 2-digit number. Find the smallest positive integer $B$ so that when we express the decimal number 61 as a base $B$ number we still get a 2-digit number.
In base 8: 758 = 7*8 + 5 = 61
In base 7 we would need: 1157 = 1*72 + 1*7 + 5 = 61
So base 8 is the smallest. i.e. B = 8
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+1836 
