If 2x = 5y and 7y=15z, what is the value of z/x expressed as a common fraction?
We can say 2.5y=x so 7y=2.8x. This means 2.8x=15z and that evaluates to z/x=2.8/15. This finally gives us the common fraction 14/75. So z/x = 14/75.
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