I think john is 10 years old hope that helps.
Answer:
Step-by-step explanation:
From the problem statement, we can setup the following equations:


where
is the current age of Shobos and
is the current age of his mother.
Substituting the first equation into the second will allow us to solve for
:




Substituting this value into the first equation gives us the age of the mother:



Arc length from A to C (red line) is the given inside angle times 2, so AC = 50*2 = 100 degrees.
A full circle is 360 degrees, so arc ABC (blue line) would be 360 - 100 = 260 degrees.
The answer is D.