ada yang bisa bantu.... thq sebelumnya

Total pupils = x
Ball games = ¹/₂.x
Hide-and-seek = ¹/₅.(1 - ¹/₂.x) = ¹/₁₀.x
Tag = 1 - ¹/₂.x - ¹/₁₀.x = ²/₅.x

Relation between tag and hide-and-seek
²/₅.x - 12 = ¹/₁₀.x
²/₅.x - ¹/₁₀.x = 12
³/₁₀.x = 12
x = (¹⁰/₃)(12)
x = 40

So, pupils played tag = (²/₅)(40) = 16