Why does the number of slices present before bob came divided by 3/4 equal the total number of slices in the pizza?

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[Originally posted in Discussions]
Why does the number of slices present before bob came divided by 3/4 (how much of the pizza it was) the total number of slices in the pizza? How does that work? Shouldn't you do some more? I don't get it.

This is because
and we found that there were 9 slices before Bob ate (based on working backwards from the 3 slices at the end).
To find the number of slices in the original pizza, divide both sides by 3/4:
Let me know if you have any more questions!
Happy Learning!
The Daily Challenge Team

[Originally posted in Discussions]
But why do you divide?

You divide because in the original equation in my prior post, the "number of slices in the whole pizza" is multiplied by 3/4:
We want to solve for the number of slices in the whole pizza, so we want to get the "whole pizza" by itself. That is why we divide by 3/4.
I hope this helps!
Happy Learning,
The Daily Challenge Team