Possible answer: A class has 42 females in it. This is 15 more than 3 times the amount of males.
Since there is 42 females, we can add that for what the equation equals.
42=
I wrote that this was 15 more than something, more being the key word for addition. Let’s add 15+
42=15+
I also wrote that this was 3 times the amount of males, times being the key word for multiplication. We don’t know how many, so we leave that as 3•x, or 3x. Let’s finish the equation with this.
42=3x+15
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