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3 years ago

6

A large ice floe is floating at a speed of 3 kilometers per hour. A polar bear leaves the floe and swims in the opposite directi

on at 9 kilometers per hour. How long will it be before the polar bear is 4 kilometers away from the floe?
How do I do this??? My teacher never teaches me!!

1 answer:

Rainbow [258]3 years ago

4 0

Ok, so the total distance will be 4 kilometers

remember, distance=speed times time

the polar bear's distance=9km/h times t or 9t
t is time in hours

the floe's distance =3km/hr times t or 3t

total disatace=polar bear disatnce+floe's distance=9t+3t=12t

so when will this distance eqal 4km?
4=12t
divide both sides by 12
4/12=t
1/3=t
about 20 mins or 1/3 hour

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