R=rate of boat in still water
c=rate of current
d=rt
since you're given that the time it takes to travel the same distance downstream and upstream, your equation will be d_1=d_2, or rt=rt
the rate upstream is r-c and the rate downstream is r+c (because the boat's and river's rates add up)
since you know t_1 and t_1 are 5 and 3, you can now set up 2 equations
<u>5*(r-c)=45</u> because (time upstream)*(rate upstream)=distance=45 miles
r-c=45/5=9
<u>3*(r+c)=45</u>
r+c=45/3=15
r-c=9 and r+c=15, so r=12 mi/h and c=3 mi/h
If you have any questions please ask
3 \frac{5}{12} / 2 \frac{1}{6}
I used to shovel snow for $5 an hour.
If ' t ' was the number of hours I spent shoveling somebody's driveway,
then ' 5t ' was the number of dollars he owed me for the job.
' t ' didn't even have to be a whole number. It worked fine with any number.
All the interior angles of a triangle always add up to 180 degrees.
3x + (2x + 20) + (4x - 20) = 180
3x + 2x + 20 + 4x - 20 = 180
3x + 2x + 4x + 20 - 20 = 180
10x = 180
x = 180/10
Therefore, x = 18
