Fill in the blanks in units (Eg 3 u) or unit equations (Eg 1 u + 2).
Bryan, Charlie and Adam have some stickers.
After Bryan's number of stickers is doubled,
Charlie's number of stickers is increased by 20 and
Adam's number of stickers is reduced by 17,
the ratio of the number of stickers of Bryan to Charlie to Adam becomes 4 : 2 : 3.
Let the number of stickers that Adam has in the end be 3 u.
- Number of stickers that Bryan has at first = _____
- Number of stickers that Charlie has at first = _____
- Number of stickers that Adam has at first = _____
- Total number of stickers that they have at first = _____
|
Bryan |
Charlie |
Adam |
Before |
2 u |
2 u - 20 |
3 u + 17 |
Change |
x 2 |
+ 20 |
- 17 |
After |
4 u |
2 u |
3 u |
(a)
Change information into units.
Number of stickers that Bryan has at first
= 4 u ÷ 2
= 2 u
(b)
Number of stickers that Charlie has at first = 2 u - 20
(c)
Number of stickers that Adam has at first = 3 u + 17
(d)
Total number of stickers that they have at first
= 2 u + 2 u - 20 + 3 u + 17
= 2 u + 2 u + 3 u - 20 + 17
= 7 u - 3
Answer(s): (a) 2 u; (b) 2 u - 20; (c) 3 u + 17; (d) 7 u - 3