Question 1070236
Their ages must all be different because they
are 3 different generations.
The possible powers of {{{ 2 }}} for their ages 
is 2, 4, 8, 16, 32, and 64 
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Which 3 of these add up to {{{ 100 }}}?
{{{ 64 + 32 + 4 = 100 }}}
Of all the numbers these are the only ones
that make sense.
The daughter was {{{ 28 }}} when the granddaughter was born.
The grandmother was {{{ 32 }}} when her daughter was
born.