The container when 3/5 filled can hold 45 marbles.
a) How many will it hold when filled?
b) How many more marbles are needed to completely fill the container?
a)
x = numbers of marbles when the container is filled
( 3 / 5 ) x = 45 Multiply both sides by 5
3 x = 5 * 45
3 x = 225 Divide both sides by 3
x = 225 / 3
x = 75
b )
2 / 5 marbles are needed to completely fill.
( 2 / 5 ) * 75 = 2 * 75 / 5 = 150 / 5 = 30
OR
a)
3 / 5 = 2 * 3 / 2 * 5 = 6 / 10 = 0.6
45 / 0.6 = 75
b)
1 - 0.6 = 0.4
0.4 * 75 = 30