tolong bantu jawab plisss

tinggi 140 cm = 10% × 40 = 4 siswa

tinggi 141 cm = 5% × 40 = 2 siswa

tinggi 142 cm = 35% × 40 = 14 siswa

tinggi 143 cm = 25% × 40 = 10 siswa

tinggi 144 cm = 25% × 40 = 10 siswa

rata² = { (4 × 140) + (2 × 141) + (14 × 142) + (10 × 143) + (10 × 144)} / (4 + 2 + 14 + 10 + 10)
= (560 + 282 + 1988 + 1430 + 1440) / 40
= 5700 / 40
= 142,5 cm