Sam is 7 years old and Anoushka is 18 years old. In how many years will Anoushka be exactly twice as old as Sam. Form and solve equation

Sam is 7 years old and Anoushka is 18 years old.
In how many years will Anoushka be exactly twice as old as Sam.
Form and solve equation.

\(\begin{array}{|rcll|} \hline \mathbf{18+n} &=& \mathbf{2(7+n)} \\ 18+n &=& 2\cdot 7 +2n \\ 18+n &=&14 +2n \quad | \quad -n \\ 18 &=&14 +2n -n \\ 18 &=&14 + n \quad | \quad - 14 \\ 18-14 &=& n \\ 4 &=& n \\ \mathbf{n} &=& \mathbf{4} \\ \hline \end{array}\)

In 4 years Anoushka  is 22 years old and Sam is 11 years old.

so Anoushka will be exactly twice as old as Sam.