Question

Alex thinks of a number. he adds 18 then divides it by 2. he gets the same answer that he would have if he had multiplied the original number by 5.

Answer 1

Let the original number for the x. Form the equation: (x+18):2=5x. Decide it: x+18=10x; x-10x=-18; -9x=-18; x=2. Answer: x=2.