Fill in the blanks in units (Eg 3 u) or unit equations (Eg 1 u + 2).
Charlie, Adam and Bryan have some beads.
After Charlie's number of beads is doubled,
Adam's number of beads is increased by 7 and
Bryan's number of beads is reduced by 2,
the ratio of the number of stickers of Charlie to Adam to Bryan becomes 6 : 9 : 4.
Let the number of stickers that Bryan has in the end be 4 u.
- Number of beads that Charlie has at first = _____
- Number of beads that Adam has at first = _____
- Number of beads that Bryan has at first = _____
- Total number of beads that they have at first = _____
|
Charlie |
Adam |
Bryan |
Before |
3 u |
9 u - 7 |
4 u + 2 |
Change |
x 2 |
+ 7 |
- 2 |
After |
6 u |
9 u |
4 u |
(a)
Change information into units.
Number of beads that Charlie has at first
= 6 u ÷ 2
= 3 u
(b)
Number of beads that Adam has at first = 9 u - 7
(c)
Number of beads that Bryan has at first = 4 u + 2
(d)
Total number of beads that they have at first
= 3 u + 9 u - 7 + 4 u + 2
= 3 u + 9 u + 4 u - 7 + 2
= 16 u - 5
Answer(s): (a) 3 u; (b) 9 u - 7; (c) 4 u + 2; (d) 16 u - 5