Ethan, Jamie, Amelia and Mason share the same hobby of collecting beads. The average number of beads collected by the 4 friends is 24. Jamie collected 7 more beads than Amelia but 18 fewer beads than Ethan. Mason collected 4 beads fewer than Amelia. Find the average number of beads collected by Jamie and Mason. Round off your answer to the nearest whole number.
Number of beads Amelia collected = 1 u
Number of beads Jamie collected = 1 u + 7
Number of beads Ethan collected = 1 u + 7 + 18 = 1 u + 25
Number of beads Mason collected = 1 u - 4

Total number of beads collected
= 4 x 24
= 96

Total number of beads collected in units
= 1 u + 1 u + 7 + 1 u + 25 + 1 u - 4
= 4 u + 28

4 u + 28 = 96
4 u = 96 - 28 = 68

1 u = 68 ÷ 4 = 17

Total number of beads collected by Jamie and Mason
= 1 u + 7 + 1 u - 4
= 2 u + 3
= 2 x 17 + 3
= 37

Average number of beads collected by Jamie and Mason
= 37 ÷ 2
≈ 19 (Round off to the nearest whole number.)

Answer(s): 19