Christian, Evan, Harper and Nathan share the same hobby of collecting beads. The average number of beads collected by the 4 friends is 25. Evan collected 6 more beads than Harper but 18 fewer beads than Christian. Nathan collected 2 beads fewer than Harper. Find the average number of beads collected by Evan, Harper and Nathan. Round off your answer to the nearest whole number.
Number of beads Harper collected = 1 u
Number of beads Evan collected = 1 u + 6
Number of beads Christian collected = 1 u + 6 + 18 = 1 u + 24
Number of beads Nathan collected = 1 u - 2

Total number of beads collected
= 4 x 25
= 100

Total number of beads collected in units
= 1 u + 1 u + 6 + 1 u + 24 + 1 u - 2
= 4 u + 28

4 u + 28 = 100
4 u = 100 - 28 = 72

1 u = 72 ÷ 4 = 18

Total number of beads collected by Evan, Harper and Nathan
= 1 u + 6 + 1 u + 1 u - 2
= 3 u + 4
= 3 x 18 + 4
= 58

Average number of beads collected by Evan, Harper and Nathan
= 58 ÷ 3
≈ 19 (Round off to the nearest whole number.)

Answer(s): 19