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