Charlie has 60 more stickers than Adam.
After Adam gives away 20 stickers,
Charlie has 5 times as many stickers as Adam.
- How many stickers does Adam have at first?
- How many stickers does Charlie have?
- How many stickers do they have altogether at first?
- How many stickers do they have altogether in the end?
|
Charlie |
Adam |
Before |
1 u + 20 + 60 |
1 u + 20 |
Change |
No change |
- 20 |
After |
5 u |
1 u |
(a)
The number of stickers that Charlie has at first and in the end remains unchanged.
Number of stickers that Charlie has at first = Number of stickers that Charlie has in the end
1 u + 20 + 60 = 5 u
1 u + 80 = 5 u
5 u - 1 u = 80
4 u = 80
1 u = 80 ÷ 4 = 20
Number of stickers that Adam has
= 1 u + 20
= 20 + 20
= 40
(b)
Number of stickers that Charlie has
= 5 u
= 5 x 20
= 100
(c)
Number of stickers that they have altogether at first
= 1 u + 20 + 60 + 1 u + 20
= 1 u + 1 u + 20 + 60 + 20
= 2 u + 100
= 2 x 20 + 100
= 40 + 100
= 140
(d)
Number of stickers that they have altogether in the end
= 5 u + 1 u
= 6 u
= 6 x 20
= 120
Answer(s): (a) 40; (b) 100; (c) 140; (d) 120