In which proportion does x have a value of 4?
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Answer:
B
Step-by-step explanation:
Using the method of cross- multiplication
A
7x = 252 ( divide both sides by 7 )
x = 36 ≠ 4
B
21x = 84 ( divide both sides by 21 )
x = 4
C
5x = 2 ( divide both sides by 5 )
x = 0.4 ≠ 4
D
5x = 200 ( divide both sides by 5 )
x = 80 ≠ 4
The proportion where x = 4 is B