A boy leaves home at 7:30 a.m and cycles to school, 6 km away, arriving at 7:45 a.m. The average speed of the boy as he cycles, in kmh, is (A) 32 (B) 24 (C) 18 (D) 16​

Respuesta :

Answer:

B) 24

Step-by-step explanation:

distance = 6 km

we want the speed in km/h, so let's turn everything into either km or h if possible

time = 7:45 am - 7: 30 am = 15 minutes

60 minutes = 1 hour

1 hour / 60 minutes = 1

15 minutes * 1 = 15 minutes * 1 hour/60 minutes = 15 / 60 hours = 1/4 hours = 0.25 hours

note that we multiply by 1 hour / 60 minutes, not 60 minutes/ 1 hour. this is because we want the minutes to cross out -- because the original is given in minutes ( 15 minutes = 15 minutes/1) and is in the numerator, we need minutes in the denominator of 1 hour/60 minutes to cross it out

km = 6

h = 0.25

km/h = 6/0.25 = 24