Fill in the blanks in units (Eg 3 u) or unit equations (Eg 1 u + 2).

Adam, Bryan and Charlie have some stickers.
After Adam's number of stickers is doubled,
Bryan's number of stickers is increased by 9 and
Charlie's number of stickers is reduced by 3,
the ratio of the number of stickers of Adam to Bryan to Charlie becomes 2 : 3 : 4.

Let the number of stickers that Charlie has in the end be 4 u.

1. Number of stickers that Adam has at first = _____
2. Number of stickers that Bryan has at first = _____
3. Number of stickers that Charlie has at first = _____
4. Total number of stickers that they have at first = _____

	Adam	Bryan	Charlie
Before	1 u	3 u - 9	4 u + 3
Change	x 2	+ 9	- 3
After	2 u	3 u	4 u

(a)
Change information into units.

Number of stickers that Adam has at first
= 2 u ÷ 2
= 1 u

(b)
Number of stickers that Bryan has at first = 3 u - 9

(c)
Number of stickers that Charlie has at first = 4 u + 3

(d)
Total number of stickers that they have at first
= 1 u + 3 u - 9 + 4 u + 3
= 1 u + 3 u + 4 u - 9 + 3 
= 8 u - 6

Answer(s): (a) 1 u; (b) 3 u - 9; (c) 4 u + 3; (d) 8 u - 6