Can someone help me with this question please??

The correct answer is 48 mph

Explain

First, 32 miles

Average speed 64 mph

T1= time for first 32 miles

distance / speed

32 miles / 64 mph = 0.5 hrs

For remaining distance = 200 miles- 32 miles = 168miles

Let average speed = x

T1 = time for rest of journey = distance / speed

168miles / x mph

Since

Total time journey is 4 hours

T1 + t2 = 4hr

Or

0.5 +168/x = 4

168/x = 4-0.5

168/ x = 3.5

X= 168/ 3.5

X= 48 mph