You work it backwards.
-- If there were 4 children and each child got 4 pieces,
then the children got (4 x 4) = 16 pieces altogether.
-- That's what was left after he took 2 pieces for himself.
So he started with (16 + 2) = <em>18 pieces</em>.
Letter B I have done this before
$4.20 / 36 = $0.11667 per potato<span>
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I believe that the answer would be 27%
