Question

quanto vale x com cálculo
1/7=×/21
4/5=12/×
5/7=×/42
×/4=15/20

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Answer 1

Explicação passo a passo:

a

1/7=×/21

multiplica em cruz

7 * x = 1 * 21

7x = 21

x = 21/7 = 3 >>>>>

b

4/5=12/×

4*x = 5 * 12

4x = 60

x = 60/4 = 15 >>>>

c

5/7=×/42

7 * x = 5 * 42

7x = 210

x = 210/7 = 30 >>>>>

d

×/4=15/20

20 * x = 4 * 15

20x = 60

x = 60/20 = 3 >>>>>>>