In April, Jean and Andy had pens in the ratio 7 : 5. In May, each of them gave away the same number of pens. Jean then had four times as many pens as Andy.
- Find the ratio of the number of pens Andy had in April to the number of pens he had in May.
- Find the ratio of the total number of pens both had in April to the total number of pens both had in May.
| |
Jean |
Andy |
Difference |
| Before |
7x3 =
21 u |
5x3 =
15 u |
2x3 =
6 u |
| Change |
- 13 u |
- 13 u |
|
| After |
4x2 =
8 u |
1x2 =
2 u |
3x2 =
6 u |
(a)
Since Jean and Andy gave away the same number of pens, the difference in the number of pens between Jean and Andy at first and in the end remains the same.
Make the difference in the number of pens at first and in the end the same. LCM of 2 and 3 is 6.
Andy's pens in April : Andy's pens in May
15 : 2
(b)
Total number of pens in April
= 21 u + 15 u
= 36 u
Total number of pens in May
= 8 u + 2 u
= 10 u
Total pens in April : Total pens in May
36 : 10
(÷2)18 : 5
Answer(s): (a) 15 : 2; (b) 18 : 5
