Ivan, Jenson and Perry had a total of 104 pens. The ratio of the number of pens that Jenson had to the number of pens that Perry had was 4 : 5. After Ivan and Jenson each gave away half of their pens, the 3 children had 77 pens left. How many pens did Jenson and Perry have in the end?
| |
Ivan |
Jenson |
Perry |
Total |
| Before |
2 p |
4 u |
5 u |
104 |
| Change |
- 1 p |
- 2 u |
|
- 27 |
| After |
1 p |
2 u |
5 u |
77 |
Total number of pens that Ivan and Jenson gave away
= 104 - 77
= 27
1 p + 2 u = 27 --- (1)
1 p + 2 u + 5 u = 77
1 p + 7 u = 77 --- (2)
(2) - (1)
(1 p + 7 u) - (1 p + 2 u) = 77 - 27
7 u - 2 u = 50
5 u = 50
1 u = 50 ÷ 5 = 10
Total number of pens that Jenson and Perry had in the end
= 2 u + 5 u
= 7 u
= 7 x 10
= 70
Answer(s): 70
