Riordan, Charlotte, Mia and Dylan share the same hobby of collecting beads. The average number of beads collected by the 4 friends is 30. Charlotte collected 7 more beads than Mia but 17 fewer beads than Riordan. Dylan collected 3 beads fewer than Mia. Find the average number of beads collected by Charlotte, Mia and Dylan. Round off your answer to the nearest whole number.
Number of beads Mia collected = 1 u
Number of beads Charlotte collected = 1 u + 7
Number of beads Riordan collected = 1 u + 7 + 17 = 1 u + 24
Number of beads Dylan collected = 1 u - 3

Total number of beads collected
= 4 x 30
= 120

Total number of beads collected in units
= 1 u + 1 u + 7 + 1 u + 24 + 1 u - 3
= 4 u + 28

4 u + 28 = 120
4 u = 120 - 28 = 92

1 u = 92 ÷ 4 = 23

Total number of beads collected by Charlotte, Mia and Dylan
= 1 u + 7 + 1 u + 1 u - 3
= 3 u + 4
= 3 x 23 + 4
= 73

Average number of beads collected by Charlotte, Mia and Dylan
= 73 ÷ 3
≈ 24 (Round off to the nearest whole number.)

Answer(s): 24