Question

Resolva as proporções: (ME AJUDEM PLMDS)

A) 8/4 = 15/x

B) 25/x = 75/3

C) 4/7 = 12/y

D) 1,4/0,7 = 2,8/F

Answer 1

a] 8/4 = 15/x

Multiplica cruzado

8x = 4.15

8x = 60

x = 60/8

x = 7,5

b] 25/x = 75/3

75x = 25.3

75x = 75

x = 75/75

x = 1

c] 4/7 = 12/y

4y = 7.12

4y = 84

y = 84/4

y = 21

 
d] 1,4/0,7 = 2,8/F

Multiplicando tudo por 10 para facilitar

14/7 = 28/10F

14.10F = 7.28

140F = 196

F = 196/140

F = 1,4