Answer:
Andy has 320 marbles while Henry has 400 marbles.
Explanation:
Although there are two people involved in this problem, we can solve it by using one variable.
Let the number of marbles that Henry has be
x
Andy has
80
%
x
and
Henry has
100
%
x
or, Andy has
0.8
x
marbles and Henry has
x
marbles
Andy now gives 80 marbles to Henry, so he has 80 fewer marbles and Andy has 80 more marbles.
Andy has
:
(
0.8
x
−
80
)
and Henry has
(x+80)
Andy now has half as many as Henry , which means that Henry has twice as many as Andy.
