Gabriel, Bryan, Jack and Aria share the same hobby of collecting buttons. The average number of buttons collected by the 4 friends is 26. Bryan collected 8 more buttons than Jack but 15 fewer buttons than Gabriel. Aria collected 3 buttons fewer than Jack. Find the average number of buttons collected by Bryan, Jack and Aria. Round off your answer to the nearest whole number.
Number of buttons Jack collected = 1 u
Number of buttons Bryan collected = 1 u + 8
Number of buttons Gabriel collected = 1 u + 8 + 15 = 1 u + 23
Number of buttons Aria collected = 1 u - 3

Total number of buttons collected
= 4 x 26
= 104

Total number of buttons collected in units
= 1 u + 1 u + 8 + 1 u + 23 + 1 u - 3
= 4 u + 28

4 u + 28 = 104
4 u = 104 - 28 = 76

1 u = 76 ÷ 4 = 19

Total number of buttons collected by Bryan, Jack and Aria
= 1 u + 8 + 1 u + 1 u - 3
= 3 u + 5
= 3 x 19 + 5
= 62

Average number of buttons collected by Bryan, Jack and Aria
= 62 ÷ 3
≈ 21 (Round off to the nearest whole number.)

Answer(s): 21