Bryan has 20 more stickers than Adam.
After Adam gives away 20 stickers,
Bryan has 5 times as many stickers as Adam.
- How many stickers does Adam have at first?
- How many stickers does Bryan have?
- How many stickers do they have altogether at first?
- How many stickers do they have altogether in the end?
|
Bryan |
Adam |
Before |
1 u + 20 + 20 |
1 u + 20 |
Change |
No change |
- 20 |
After |
5 u |
1 u |
(a)
The number of stickers that Bryan has at first and in the end remains unchanged.
Number of stickers that Bryan has at first = Number of stickers that Bryan has in the end
1 u + 20 + 20 = 5 u
1 u + 40 = 5 u
5 u - 1 u = 40
4 u = 40
1 u = 40 ÷ 4 = 10
Number of stickers that Adam has
= 1 u + 20
= 10 + 20
= 30
(b)
Number of stickers that Bryan has
= 5 u
= 5 x 10
= 50
(c)
Number of stickers that they have altogether at first
= 1 u + 20 + 20 + 1 u + 20
= 1 u + 1 u + 20 + 20 + 20
= 2 u + 60
= 2 x 10 + 60
= 20 + 60
= 80
(d)
Number of stickers that they have altogether in the end
= 5 u + 1 u
= 6 u
= 6 x 10
= 60
Answer(s): (a) 30; (b) 50; (c) 80; (d) 60