the sum of the ages of Sam and Tomas is 27 years. Seven years ago, Tomas was three years more than one- fourth as old as Sam. find there present age.
The sum of the ages of Sam and Tomas is 27 years.
Seven years ago, Tomas was three years more than one- fourth as old as Sam.
Find there present age.
x = sam age
y = thomas age
\(\begin{array}{|rclcrcl|} \hline x+y &=& 27 \quad \text{or} \quad \mathbf{y = 27-x} \\\\ \mathbf{y-7} &=& \mathbf{\dfrac{1}{4}(x-7) + 3} \\ y &=& \dfrac{1}{4}(x-7) + 3 +7 \\\\ y &=& \dfrac{1}{4}(x-7) + 10\quad | \quad y = 27-x \\\\ 27-x &=& \dfrac{1}{4}(x-7) + 10 \\\\ -x &=& \dfrac{1}{4}(x-7) + 10-27 \\\\ -x &=& \dfrac{1}{4}(x-7) -17 \\\\ x + \dfrac{1}{4}(x-7) &=& 17 \quad | \quad *4 \\\\ 4x + x-7 &=& 4*17 \\\\ 5x &=& 4*17 +7 \\\\ 5x &=& 75 \\\\ \mathbf{x} &=& \mathbf{15} \\ \hline \\ \mathbf{y} &=& \mathbf{27-x} \\ y &=& 27-15 \\ \mathbf{y} &=& \mathbf{12} \\ \hline \end{array}\)
sam is 15 and thomas is 12