Acontainer holds 8 gallons of water. if 4 5 of a gallon is added to the container each hour, how many hours would it take to fill the container?

So we know that 4.5 x 2 = 9, so it wouldn't work.
And because it wouldn't work it wouldn't take 2 hours.

4.5 = 1 hour and 9 = 2.

So we'll have to divide 4.5 by 2 by first turning it into a fraction.

4.5 = 4 1/2
4 1/2 ÷ 2 = 2 1/4
2 1/4 = 2.25
2.25 = 30 minutes.
4.5 + 2.25 = 6.75.
1 hour + 30 mins. = 1 hour and 30 minutes.

However we can still keep going.

2.25 ÷ 2 = 1.125
1.125 in fraction form is 1 1/8
1.125  = 15 minutes
1 hour and 30 minutes  + 15 minutes = 1 hour and 45 minutes.
6.75 + 1.125 = 7.875
7.875 in fraction form is 7 7/8

Your answer would be it would take 1 hour and 45 minutes.