Fill in the blanks in units, decimal units or unit equations. (Eg 3 u OR 1.2 u OR 1 u + 2)

Adam, Bryan, and Charlie have some marbles.
After Adam's number of marbles is doubled,
Bryan's number of marbles is increased by 20 and
Charlie's number of marbles is reduced by 18,
the ratio of the number of stickers of Adam to Bryan to Charlie becomes the same.

Let the number of marbles that Adam has in the end be 1 u.

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

	Adam	Bryan	Charlie
Before	0.5 u	1 u - 20	1 u + 18
Change	x 2	+ 20	- 18
After	1 u	1 u	1 u

(a)
Change information into units.

Number of marbles that Adam has at first
= 1 u ÷ 2
= 0.5 u

(b)
Number of marbles that Bryan has at first = 1 u - 20

(c)
Number of marbles that Charlie has at first = 1 u + 18

(d)
Total number of marbles that they have at first
= 0.5 u + 1 u - 20 + 1 u + 18
= 0.5 u + 1 u + 1 u - 20 + 18
= 2.5 u - 2

Answer(s): (a) 0.5 u; (b) 1 u - 20; (c) 1 u + 18; (d) 2.5 u - 2