Question 888663
1.75 h=60+45=105 minutes
105-90=15 minutes running

4/1.75 =2.2857 kmph average for the 1.75  hours

per hour
a+b=.25
r*a=.5
2r*b=3.5

a=0.0555556 hr b,   b=0.194444 hr,   r=9 kph before his nap.

per minute
a+b=15
r*a=.5
2r*b=3.5

a=3.33333 minutes before nap,   b=11.6667 minutes after nap,   r=0.15 km  per minute before his nap