It's a ratio, which, if understood, [ is very simple:
First set the ratio up:
put the problem into ratios aka fractions (I'm limited to " / " lines - those are meant as fraction lines)
30.788/x = 35.8%/100%
What this means verbally is: 30.788 of x is as 35.8% is of 100%. The number we do not know is x.
So now we solve. First divide 35.8% by 100%, takes away the percent % and gives you 0,358, a decimal.
So now you have: 30.788/x = 0.358
Move the x over by multiplying 0.358 with x: 30.788 = 0.358x
And now, to get the x alone, divide 30.788 by 0.358, and you get x = 86.
Once you understand WHY you do this, instead of going through writing out these steps you would naturally divide 35.8% by 100% (converting from percent to decimal form) and then divide 30.788 by 0.358.
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