Ok so the first thing you are going to do is chang the percentage into a decimal. 12 percent would change into 0.12, because in order to change a percentage into a decimal you move the decimal two places to the left. Next you would multiply 0.12 by 45 which gives you 5.4. But we are not done yet. By multiplying 0.12 x 45 we find how much weight she has gained. So our next and final step should be add 5.4 to 45 which gives us 50.4. Therefore your answer should be 50.4kg
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