<PRE><B>Question 753485</B>
Two ships are sailing out from the same spot at the same time. 
The first ship is sailing due east at 18km/h and the other due north at 25km/h. How fast are the ships moving away from eachother 4 hours later?
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East-bound ship DATA: rate = 18 km/hr ; time = 4 hrs ; dist = 18*4 = 72 km
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North-bound ship: rate = 25 km/hr ; rime = 4 hrs ; dist = 4*25 = 100 km
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Distance from ship to ship: sqrt[72^2+100^2] = 123.33 km
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rate = 123.33 km/ 4 hrs = 30.8 mph
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Cheers,
Stan H.

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