Can someone help with this?
A person drives at a constant speed of 97km/h except for a break that he takes which is 26.4 minutes long. If the average speed of the trip is 64km/h...
How long did the whole trip take?
How far does the person go?
speed = distance / time
Average speed also = distance / time
Assume two chunks of time: t1 spent driving at 97 km/hr and t2=26.4min spend driving at 0 km/hr
Convert break to hours: 26.4/60 = 0.44 hr
Average the speeds: (s1 + s2) / (t1 + 0.44)
(97 + 0) / (t1 + 0.44) = 64
t1 = 97/64 - 0.44 = 1.075625
Or, total time = 1.515625 hr and total distance = 64 km/hr * 1.075625 hr = 68.84 km.
But, I may have done it wrong. It's late and I haven't checked for mistakes...
Last edited by ryos (2005-10-18 18:15:43)
El que pega primero pega dos veces.
Checked, found right.
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I love maths. It's so fun and exciting. Please tell me more. Oh maths!! (Jelly babies)
Insomnia...? You have a jelly baby fan friend.
You can combine maths and jelly babies. Count them.
Actually I edited his post as he was being abusive. *I hate maths* was what he said. So I changed it.
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Oh, and they would probably be the first to notice if they didn't get the right change.