Question

Add brackets to make this statement true: `13+50 -: 12 xx 2 -15 =7`?

Answer 1

`(13+50) -: (12 xx 2 -15) =63/(24-15)=63/9=7`

Explanation:

We want to add brackets to make this statement true:

`13+50 -: 12 xx 2 -15 =7`

The first thing that catches my eye is that we have a division sign that currently has 50 being divided by 12. I think we're going to want that result be a whole number (so no remainders or fractions). So let's work with that idea.

How can we do this? If I bracket `12xx2`, I get `50/24` - still no good.

How about if I bracket `13+50`. I get `63/12` or `63/24` - neither of those work.

But! if I can get the denominator to 9, then it will divide evenly into the 63 (and will also be our final answer of 7). And we can achieve that by putting the `-15` in the denominator bracket as well:

`(13+50) -: (12 xx 2 -15) =63/(24-15)=63/9=7`

Answer 2

`(13+50)/(12*2-15)=7`

Explanation:

You can either: Write a program to try every single parenthesis combination to see which one works.

Or: You can logic it out based on guesses. Remember, teachers rarely will give ugly fractions. You are trying to make numbers (such as 63) which appear on a times table.