Answer: 22
Explanation:
this problem is solved by a system of equations
Let Arthur’s current age be represented by:a
His brother’s current age will be represented by: b
The first equation will be:
a = 7 + b
The second equation will be:
a + 8 = 2b
now we solve for the equations. Plug in a = 7+b into a in the second equation.
So now we have
b+7+8=2b
Simplify:
B+15=2b
15=b
We aren’t done yet though
Arthur’s brother is 15 years old but since he is 7 years older we need to add 7 to 15
Hence, Arthur is 22 years old.