Answer:
2 hours
Step-by-step explanation:
The relation between time, speed, and distance is ...
time = distance/speed
For a kayak speed of k miles per hour in still water, the speed upstream is (k-2) and the speed downstream is (k+2). Over the distances given, the times are the same, so we can write ...
10/(k-2) = 14/(k+2)
Multiplying by (k+2)(k-2) gives ...
10(k+2) = 14(k -2)
10k +20 = 14k -28 . . . . . eliminate parentheses
48 = 4k . . . . . . . . . . . . . . add 28-10k
12 = k
Then the time for 28 miles downstream is ...
time = 28 / (12 +2) = 2 . . . . hours
It will take the person 2 hours to kayak 28 miles downstream.
Hope this helps!!!!!!!!!!
64
+43
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107
the 4 and 3 on the right only adds up to 7... if the numbers add up to be 10 more you always take the left number and add it to the left side of your adding chart... if not just add from right to left