SOLUTION: if x/3y=4/7 and z/5y=2/21, then x/z=?

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Question 620728: if x/3y=4/7 and z/5y=2/21, then x/z=?
Answer by Maths68(1474) About Me  (Show Source):
You can put this solution on YOUR website!
x%2F3y=4%2F7
z%2F5y=2%2F21
x%2Fz=%22%3F%22

x%2F3y=4%2F7
x=4%283y%29%2F7
x=12y%2F7.............(1)


z%2F5y=2%2F21
z=%285y%292%2F21
z=10y%2F21..............(1)
Divide x by z, we have
x%2Fz=%2812y%2F7%29%2F%2810y%2F21%29
x%2Fz=%2812y%2F7%29%2821%2F10y%29
x%2Fz=%28cross%2812y%29%2Fcross%287%29%29%28cross%2821%29%2Fcross%2810y%29%29
x%2Fz=%286%2F1%29%283%2F5%29
x%2Fz=18%2F5
x%2Fz=3%263%2F5