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

Adam, Charlie and Bryan have some stickers.
After Adam's number of stickers is doubled,
Charlie's number of stickers is increased by 16 and
Bryan's number of stickers is reduced by 13,
the ratio of the number of stickers of Adam to Charlie to Bryan becomes 8 : 7 : 7.

Let the number of stickers that Bryan has in the end be 7 u.

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

	Adam	Charlie	Bryan
Before	4 u	7 u - 16	7 u + 13
Change	x 2	+ 16	- 13
After	8 u	7 u	7 u

(a)
Change information into units.

Number of stickers that Adam has at first
= 8 u ÷ 2
= 4 u

(b)
Number of stickers that Charlie has at first = 7 u - 16

(c)
Number of stickers that Bryan has at first = 7 u + 13

(d)
Total number of stickers that they have at first
= 4 u + 7 u - 16 + 7 u + 13
= 4 u + 7 u + 7 u - 16 + 13 
= 18 u - 3

Answer(s): (a) 4 u; (b) 7 u - 16; (c) 7 u + 13; (d) 18 u - 3