Question

Kang Tae Moo thinks of a number. He adds 13 to the number. He multiples the result by 3. This gives the same result as if he multiplied the number by 9 and then subtracted 3. What number is Kang Tae Moo thinking of?

Answer 1

7

Explanation:

We can setup this equation as x representing his number. (x+13) * 3 = 9x -3.

Now, we just need to solve for x.

3(x+13)=9x-3

x+13=3x-1

14=2x

x=7