The average number of beads that Adam and Charlie have is 6.
The average number of beads that Charlie and Bryan have is 5.
The average number of beads that Bryan and Adam have is 9.

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

(a)
Let the number of beads that Adam has be A.
Let the number of beads that Charlie has be C.
Let the number of beads that Bryan has be B.

A + C = 2 x 6 = 12 --- (1)
C + B = 2 x 5 = 10 --- (2)
A + B = 2 x 9 = 18 --- (3)

(A + C) + (C + B) + (A + B) = 12 + 10 + 18
2 x (A + C + B) = 40
A + C + B = 40 ÷ 2
A + C + B = 20 --- (4)

Substitute (2) into (4).
A + C + B = 20
A + 10 = 20

A = 20 - 10 = 10

Number of beads that Adam has = 10

(b)
Substitute A = 10 into (1).
A + C = 12
10 + C = 12 

C = 12 - 10 = 2

Number of beads that Charlie has = 2

(c)
Substitute Charlie's beads = 2 into (2).
C + B = 10
2 + B = 10

B = 10 - 2 = 8

Number of beads that Bryan has = 8

Answer(s): (a) 10; (b) 2; (c) 8