Question 166580
    fran swims at a speed of 2.2 km/h in still water. the lazy river flows at a speed of 0.4 km/h. how long will it take fran to swim 0.9 km upstream?
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We will need to apply the "distance" formula:
d = rt
where
d is distance
r is rate or speed
t is time
.
Reordering the equation, we solve for 't':
t = d/r
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Fran's rate (r) is:
2.2 - 0.4 = 1.8 km/h
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Therefore:
.9/1.8 = 0.5 hours