To make the proportion true, x would have to equal 25
This proportion basically say "7 is to 35, as x is to 125"
To find out what x equals, let's divide 35 by 7. That gets us 5. So, now we know that our ratio between proportions is 5. That means that x * 5 =125. So, to find x we divide 125 by 5 and that gives us 25 for x.
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