The average number of stickers that Adam and Bryan have is 23.
The average number of stickers that Adam and Charlie have is 58.
The number of stickers that Bryan has is ²₉ as many as Charlie.

1. How many stickers does Adam have?
2. How many stickers does Bryan have?
3. How many stickers does Charlie have?

(a)
Number of stickers that Adam and Bryan has
= 2 x 23
= 46

Number of stickers that Adam and Charlie has
= 2 x 58
= 116

Number of stickers that Bryan has = 2 u
Number of stickers that Charlie has = 9 u

Let the number of Adam's stickers be A.
Let the number of Bryan's stickers be B.
Let the number of Charlie's stickers be C.


A + B = 46
A + 2 u = 46 --- (1)

A + C = 116
A + 9 u = 116 --- (2)

(2) - (1)
(A + 9 u) - (A + 2 u ) = 116 - 46
A + 9 u - A - 2 u = 70
A - A + 9 u - 2 u = 70

7 u = 70

1 u = 70 ÷ 7 = 10

Substitute 1 u = 10 into (1).
A + 2 x 10 = 46
A + 20 = 46
A = 46 - 20 = 26

Number of stickers that Adam has = 26

(b)
Number of stickers that Bryan has
= 2 u
= 2 x 10
= 20

(c)
Number of stickers that Charlie has
= 9 u
= 9 x 10
= 90

Answer(s): (a) 26; (b) 20; (c) 90