Let b be the number of boys and g be the number of girls originally.
(1+35%)b=(1+10%)gbg=(1+10%)(1+35%)=1.11.35=2227∴b:g=22:27
I divided (1+35%)g on each side of Step 1 so I get step 2. Then I simplify the fraction on the right hand side of the equal sign to make the numerator and denominator both integers. Then I used the definition of ratio to get the conclusion.
The definition: x:y=xy
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