Adam has 900 stickers.
Bryan has 400 stickers.
Bryan receives some stickers from Adam.
Now, Adam has 100 more stickers than Bryan.

1. How many stickers does Adam have in the end?
2. How many stickers does Bryan have in the end?
3. How many stickers does Adam give to Bryan?

	Adam	Bryan	Total
Before	900	400	1300
Change	- ?	+ ?
After	1 u + 100	1 u	2 u + 100

(a)
At first
Number of stickers that Adam has = 900
Number of stickers that Bryan has = 400
Total number of stickers = 900 + 400 = 1300

In the end
Number of stickers that Adam has = 1 u + 100
Number of stickers that Bryan has = 1 u

Total number of stickers
= 1 u + 1 u + 100
= 2 u + 100

The total number of stickers at first and in the end remains unchanged.
Total number of stickers in the end = Total number of stickers at first

2 u + 100 = 1300
2 u = 1300 - 100 = 1200

1 u = 1200 ÷ 2 = 600

Number of stickers that Adam in the end
= 1 u + 100
= 600 + 100
= 700

(b)
Number of stickers that Bryan has in the end
= 1 u
= 600

(c)
Number of stickers that Adam gives to Bryan
= 600 - 400
= 200

Answer(s): (a) 700; (b) 600; (c) 200