Author Topic: Math attack  (Read 1337 times)

nid404

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Math attack
« on: May 08, 2009, 05:15:26 am »
These are two similar questions and they r so totally not comprehensive .....or......rather I don't know how to do it.

1) A car travelling at 90  km/h is 500m behind another car travelling at 70km/h in the same direction.How long will it take the first car to catch the second?

2) A train of length 100m is moving at a speed of 50km/h. A horse is running alongside the train at a speed of 56km/h. How long will it take for the horse to overtake the train?


PLzzzzzzz give the steps and explain how it is to be done.

Thanx

Offline Ghost Of Highbury

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Re: Math attack
« Reply #1 on: May 08, 2009, 05:55:43 am »
Ans 1.) first subtract both the speeds i.e => 90-70= 20...i.e the car going at 90km/h gains 20 km every hour......therefore to cover a distance of .5 km at a speed of 20km/h will take 0.5/20 hours = 1.5 minutes...
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Offline Ghost Of Highbury

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Re: Math attack
« Reply #2 on: May 08, 2009, 05:59:34 am »
try the same method for the second sum.....

Ans = .1 km (100 m) / 56-50 = .1/6 (hours)....for minutes .1/6*60 = 1 minute..
Ans - 1 minute
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Re: Math attack
« Reply #3 on: May 08, 2009, 06:07:44 am »
are these sums taken from any past paper....or a book....i guess david rayner
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