Adam has 86 stickers.
After ²₇ of the red stickers is given away and
another 10 blue stickers are bought,
there is an equal number of red and blue stickers.

1. How many red stickers are there in the end?
2. How many less blue stickers than red stickers are there at first?
3. How many red stickers are given away?

	Red	Blue
Before	7 u	5 u - 10
Change	- 2 u	+ 10
After	5 u	5 u

(a)
Fraction of the red stickers left
= 1 - ²₇
= ⁵₇

The number of red stickers and blue stickers in the end is the same.

Total number of stickers at first
= 7 u + 5 u - 10
= 12 u - 10

12 u - 10 = 86
12 u = 86 + 10
12 u = 96

1 u = 96 ÷ 12 = 8

Number of red stickers in the end
= 5 u
= 5 x 8
= 40

(b)
Number of less blue stickers than red stickers at first
= 7 u - (5 u - 10)
= 7 u - 5 u + 10
= 2 u + 10
= 2 x 8 + 10
= 16 + 10
= 26

(c)
Number of red stickers given away
= 2 u
= 2 x 8
= 16

Answer(s): (a) 40; (b) 26; (c) 16