Question

I thought of a number, added 4 5 /7 to it, and got the number 12 times as big as my original number. What was my number?

Answer 1

3/7

Explanation:

Lets assume the unknown number is x. x+4 5/7=12x

to get all your variables on one side, subtract x.

4 5/7=11n

Since mixed numbers are useless here, convert it to a improper fraction. 33/7=11x

Then, divide both sides by 11.

33/7÷11=3/7

11x÷11=x

x=3/7