Question

A number is doubled and then increased by five. The result is eighty-seven. What is the original number?

Answer 1

ANSWER

The original number is 41

EXPLANATION

Let 'x' be the number. If it's doubled it means it's multiplied by 2: 2x. Then it's increased by 5, which means we have to add 5: 2x + 5. And this equals to 87:

$2x+5=87$

Solving for x:

$\begin{gathered} 2x=87-5 \\ 2x=82 \\ x=\frac{82}{2} \\ x=41 \end{gathered}$