home if they want to reach school,which is 5km away, at the same time?
2007-10-25 03:32:17 · 3 answers · asked by sakira 1 in Science & Mathematics ➔ Mathematics
Bill runs 10 km per hour
The distance is 5km
Bill will arrive in: 5km/10km per hour = 0.5 hour
= 0.5hr x 60mins/hr =30mins
Ted runs 8 km per hour
The distance is 5 km
Ted will arrive in: 5km / 8 km per hour = 0.625 hour = 0.625hr x 60 mins/hr = 37.5 mins.
To reach school at the same time, Bill should start running after Ted ran for:
37.5mins - 30 mins = 7.5 mins.
2007-10-25 03:47:17 · answer #1 · answered by A.D.S 2 · 0⤊ 0⤋
it takes ted 5/8 hr = 0.625 hr
and it take bill 5/10 hr = 0.5 hr
so he could leace 0.625 - 0.5 = 0.125 = 1/8 hr later
2007-10-25 10:43:42 · answer #2 · answered by norman 7 · 0⤊ 0⤋
distance = rate * time
distance/rate= time
you have the rates and distances, just plug and chug
you should get 7.5 minutes
2007-10-25 10:42:25 · answer #3 · answered by Anonymous · 0⤊ 0⤋