Question

ou are to drive to an interview in another town, at a distance of 290 km on an expressway. The interview is at 11:15 a.m. You plan to drive at 100 km/h, so you leave at 8:00 a.m. to allow some extra time. You drive at that speed for the first 120 km, but then construction work forces you to slow to 44.0 km/h for 43.0 km. What would be the least speed needed for the rest of the trip to arrive in time for the interview

Answer 1

Answer:

Speed remaining = 119.059 km/hr

Step-by-step explanation:

Distance to cover is 290km

Interview time= 11:15 am

Time left = 8:00 am

Time to spend in the road = 11:15-8:00= 3 hrs 15 minutes

For the first 120 km speed is = 100km/hr

Time spent = 120/100

Time spent = 1.2 hrs

Time spent 1 hour 12 min

For the 43km speed is 44km/hr

Time spent = 43/44

Time spent = 0.97727 hrs

Time spent = 58.64 min

Time spent = 58 min 38 seconds 40 millisecond

Distance covered = 120+43

Distance covered = 163km

Distance remaining is 290-163= 127km

Total Time spent = 1.2+0.97727

Total Time spent = 2.17727 hrs

Total Time spent = 2 hrs 11 min

Time remaining is 3hrs 15min - 2hrs 11 min

Time remaining = 1 hr 4min

Time remaining= 1.06667

Least speed remaining is

Speed= 127/1.06667

Speed = 119.059 km/hr

Thank you