Julian, Michael and Perry had a total of 64 pens. The ratio of the number of pens that Michael had to the number of pens that Perry had was 6 : 7. After Julian and Michael each gave away half of their pens, the 3 children had 46 pens left. How many pens did Michael and Perry have in the end?
| |
Julian |
Michael |
Perry |
Total |
| Before |
2 p |
6 u |
7 u |
64 |
| Change |
- 1 p |
- 3 u |
|
- 18 |
| After |
1 p |
3 u |
7 u |
46 |
Total number of pens that Julian and Michael gave away
= 64 - 46
= 18
1 p + 3 u = 18 --- (1)
1 p + 3 u + 7 u = 46
1 p + 10 u = 46 --- (2)
(2) - (1)
(1 p + 10 u) - (1 p + 3 u) = 46 - 18
10 u - 3 u = 28
7 u = 28
1 u = 28 ÷ 7 = 4
Total number of pens that Michael and Perry had in the end
= 3 u + 7 u
= 10 u
= 10 x 4
= 40
Answer(s): 40
