Question

Nathan wants you to solve this puzzle: " I am thinking of a number. If you divide my number my 3 and add -3 you will get 4. What is my number. Show all your work

Answer 1

number is 21

let the number be n then dividing by 3 gives $\frac{n}{3}$ and adding - 3 gives

$\frac{n}{3}$ - 3 = 4 ( add 3 to both sides )

$\frac{n}{3}$ = 7 ( multiply both sides by 3 )

n = 3 × 7 = 21