What is the mystery number? If I subtract 1 / 2 of it, then multiply by 3, and then add 2, the end result is 26.
This is an easy problem to solve if we look at it algebraically. We need re-write this problem using numbers and symbols.
Investigation/Exploration of the Problem
Let's call the mystery number x.
We now that we need to subtract 1/2 of the mystery number. We can write this as .5x. We need to multiply .5x by 3 then add 2 and the result is 26.
So our problem written algebraically is
(.5x)3 + 2 = 26
Now we just need to solve for x to get the mystery number.
First we simplify: (.5x)3 + 2 = 26
and the result is 1.5 x + 2 = 26
We now subtract 2 from both sides and the result is
1.5x = 24
x = 16
We can check to see if we are correct by plugging 16 into the problem. If we subtract half of 16 we are left with 8. 8 times 3 is equal to 24 and 24 + 2 = 26.
Memorial Middle School