Dana had 5 times as many pens as stamps. After she used 129 pens and 6 stamps, there were twice as many stamps as pens.
- How many pens did Dana have in the end?
- How many stamps did Dana have at first?
| |
Pens |
Stamps |
Comparing pens
and stamps at first |
5 p
|
1 p
|
| Before |
1 u + 129 |
2 u + 6 |
| Change |
- 129 |
- 6 |
| After |
1 u |
2 u |
(a)
1 u + 129 = 5 p --- (1)
2 u + 6 = 1 p --- (2)
(2)
x 5
10 u + 30 = 5 p ---(3)
(3) = (1)
10 u + 30 = 1 u + 129
10 u - 1 u = 129 - 30
9 u = 99
1 u = 99 ÷ 9 = 11
Number of pens that Dana had in the end
= 1 u
= 11
(b)
Number of stamps that Dana had at first
= 2 u + 6
= 2 x 11 + 6
= 22 + 6
= 28
Answer(s): (a) 11; (b) 28
