Fill in the blanks in units (Eg 3 u) or unit equations (Eg 1 u + 2).
Bryan, Charlie and Adam have some beads.
After Bryan's number of beads is doubled,
Charlie's number of beads is increased by 7 and
Adam's number of beads is reduced by 3,
the ratio of the number of stickers of Bryan to Charlie to Adam becomes 8 : 2 : 1.
Let the number of stickers that Adam has in the end be 1 u.
- Number of beads that Bryan has at first = _____
- Number of beads that Charlie has at first = _____
- Number of beads that Adam has at first = _____
- Total number of beads that they have at first = _____
|
Bryan |
Charlie |
Adam |
Before |
4 u |
2 u - 7 |
1 u + 3 |
Change |
x 2 |
+ 7 |
- 3 |
After |
8 u |
2 u |
1 u |
(a)
Change information into units.
Number of beads that Bryan has at first
= 8 u ÷ 2
= 4 u
(b)
Number of beads that Charlie has at first = 2 u - 7
(c)
Number of beads that Adam has at first = 1 u + 3
(d)
Total number of beads that they have at first
= 4 u + 2 u - 7 + 1 u + 3
= 4 u + 2 u + 1 u - 7 + 3
= 7 u - 4
Answer(s): (a) 4 u; (b) 2 u - 7; (c) 1 u + 3; (d) 7 u - 4