First you must find the unit rate, so a 45 divided by 6 is 7.5, so then, multiply that by 10, 10 times 7.5 is 75, move the decimal place up, now you have the base rate, you can find any amount, so with these questions, all you must do is find the unit rate, in this case, the unit rate is 7.5, the unit rate will always be the ratio of one unit to the value of the unit, seen as ( 1-7.5 ) here.
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