I believe you're solving for the pie crust surrounding the pie. If so, use the circumference formula which is 2*pi*r. The circumference is the border of the circle.
Let x be the number of hours Bob needs to travel on the second day. The equation of Bob's journey is as follows,
592 = 187 + 52x
Solving for x from this equation gives x = 7.788 hours.
Thus, Bob needs to travel for almost 8 hours on the second day. The answer is letter B. 8 hours.
A + b = 6
a - b = 4
We substract those equations, we get:
2b = 2 (dividing both sides with 2)
b = 1
a = b + 4 (look at second aquations)
= 1 + 4
= 5
