Sandy Wood
Brain Game: Well Do Ya?
by Sandy Wood - July 16, 2010 - 7:30 AM

THE SOLUTION:

133.

Each entry is a progressively-larger odd number whose digits total 7.

7 = 7
2+5 = 7
4+3 = 7
6+1 = 7
1+1+5 = 7, so…
1+3+3 = 7.

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