There were some pens in Box P and Box Q. After Tommy transferred
15 of the pens from Box P to Box Q, the ratio of the number of pens in Box P to that in Box Q changed to 1 : 5. Find the ratio of the numbers of pens in Box Q to the number of pens in Box P at first.
|
Box P |
Box Q |
Before |
5x1 = 5 u |
19 u |
Change |
- 1x1 = - 1 u |
+ 1 u |
After |
4x1 = 4 u |
|
Comparing Box P and Box Q in the end |
1x4 = 4 u |
5x4 = 20 u |
The number of pens in Box P in the end is repeated. Make the number of pens in Box P in the end the same. LCM of 4 and 1 is 4.
At first
Box Q : Box P
19: 5
Answer(s): 19: 5