A box contained gold and grey stamps. There were 60% more gold stamps than grey stamps. When 13 stamps were removed from the box, the amount of gold stamps decreased by 25% and the amount of grey stamps decreased 90%. How many stamps were in the box in the end?
|
Gold stamps |
Grey stamps |
Total stamps |
Before |
8 u |
5 u |
13 u |
Change |
- 2 u |
- 4.5 u |
- 6.5 u |
After |
6 u |
0.5 u |
6.5 u |
100% + 60% = 160%
160% =
160100 =
85Number of gold stamps that were removed from the box
= 25% x 8 u
=
25100 x 8 u
= 2 u
Number of grey stamps that were removed from the box
= 90% x 5 u
=
90100 x 5 u
= 4.5 u
Total number of stamps that were removed from the box
= 2 u + 4.5 u
= 6.5 u
6.5 u = 13
1 u = 13 ÷ 6.5 = 2
Number of stamps in the box in the end
= 6 u + 0.5
= 6.5 u
= 6.5 x 2
= 13
Answer(s): 13