Question

You start driving from Austin to Houston with a constant speed of 120km/hr (75 mph). After 1.5 hr you stop for 0.5 hr. Then you continue driving with a new constant speed v2 and reach Houston 45 mins later. If the total distance from Austin to Houston is 265km, what is the speed v2?

Answer 1

Answer:

113.33 km/hr

Step-by-step explanation:

Given that :

From Austin

Drive 1 : Speed of 120km/hr for 1.5 hours

Stop time = 0.5 hour

Drive 2 : speed of v2 for 45 minutes to finally reach Houston

Total distance (Austin to Houston) = 265 km

Total distance : (distance on drive + distance on second drive)

Distance = speed * time

(120 * 1.5) + (v2 * 45/60) = 265

180 + 0.75v2 = 265

0.75v2 = 265 - 180

0.75v2 = 85

v2 = 85 / 0.75

v2 = 113.33km/hr

v2 = 85 / 0.75

v2 =