Question

Se 9m de tecido custam R$17,00, então
a)Quanto custam 12,5m desse tecido?

Answer 1

R$ 17,00 ÷ 9 m =
R$ 17,00 ÷ 9 =
R$ 1,888888888888889 (valor de 1 m)
R$ 1,888888888888889 ÷ 100 = 0,0188888888888889 (valor de 1 cm)
12,5 x 100 = 1250 (cm )
R$ 0,0188888888888889 x 1250 =  23,61111111111113
R: 12,5 m custam R$ 23,61111111111113.

Answer 2

9 ------------------------- 17
12,5 --------------------- x
9x = 17 . 12,5
9x = 212,5
x = 212,5/9
x = 23,61