Question

A cyclist rides 24 km at 16 km per hour and a further 36 km at 15 km per hour. Find his average speed for the journey.

Answer 1

Step-by-step explanation:

case 1

given d =24 km

speed =16 kmper hr

also

case2

given d = 36km

speed = 15km/hr

avg speed = total distance/ total time

total distance = 24+36= 60 km

total time = t1+t2

s= d/t therefore t= d/s

t1 = 24/16=3/2= 1.5 hr

t2= 36/15= 2.4 hr

therefortotal time= 3.9 hr

therefore avg speed= 60/3.9

=15.39 km/hr