Question
While on vacation, Kevin went for a swim in a nearby lake. Swimming against the current, it took him 8 minutes to swim 200 meters. Swimming back to shore with the current took half as long. Find Kevin's average swimming speed and the speed of the lake's cuurent.
Answers
Let the speed of the current be y m/min
let Kevin's rate of swimming be x m/min
against the current: 8(x-y) = 200
with the current : 4(x+y) = 200
from the first 8x - 8y = 200 reduced to
x-y = 25
from the second equation x + y = 50
add them: 2x = 75
x = 37.5 m/min
subbing back in the second
y = 12.5
So the lake's current was 12.5 m/min
and his rate of swimming in still water would be 37.5 m/min
let Kevin's rate of swimming be x m/min
against the current: 8(x-y) = 200
with the current : 4(x+y) = 200
from the first 8x - 8y = 200 reduced to
x-y = 25
from the second equation x + y = 50
add them: 2x = 75
x = 37.5 m/min
subbing back in the second
y = 12.5
So the lake's current was 12.5 m/min
and his rate of swimming in still water would be 37.5 m/min
I NEED HELP IN CONVERTING 33/50 INTO A DECIMAL
Ms. Sue
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