Charlie has 2 times as many stickers as Bryan.
After Bryan gives away 90 stickers,
Charlie has 5 times as many as Bryan.

1. How many stickers does Bryan have in the end?
2. How many stickers does Charlie have?
3. How many stickers do they have altogether at first?
4. How many stickers do they have altogether in the end?

	Charlie	Bryan
Before	10 u	5 u
Change	No change	- 90
After	10 u	2 u

(a)
The number of stickers Charlie has at first and in the end remains unchanged.
Make the number of stickers Charlie has the same using LCM of 2 and 5 
LCM of 2 and 5 = 10

Number of stickers that Bryan gives away
= 5 u - 2 u
= 3 u

3 u = 90

1 u = 90 ÷ 3 = 30

Number of stickers that Bryan has in the end
= 2 u
= 2 x 30
= 60

(b)
Number of stickers that Charlie has
= 10 u
= 10 × 30
= 300

(c)
Number of stickers that they have at first
= 10 u + 5 u
= 15 u
= 15 x 30
= 450

(d)
Number of stickers that they have in the end
= 10 u + 2 u
= 12 u
= 12 x 30
= 360

Answer(s): (a) 60; (b) 300; (c) 450; (d) 360