A fisherman can row upstream at 2 mph and downstream at 8 mph. He started rowing upstream until he got tired and then rowed downstream to his starting point. How far did the fisherman row if the entire trip took 7 hours?
distance = rate x time
or
d = rt
However, the information given includes the rates and the total time of the trip.
So, solve the formula, d = rt for t (time). You'll see why in a little bit!
d = rt {distance, rate, time formula}
t = d/r {solved for t.....time equals distance divided by rate}
Now, apply that to what is given to you.
d = distance the point he got tired {which is the same distance upstream and downstream}
Remember, t = d/r {the time is the distance divided by the rate}
d/2 + d/8 = 7 {the two times are d/2 and d/8....distance divided by rate}
4d + d = 56 {multiplied entire equation by 8 to eliminate fractions}
5d = 56 {combined like terms}
d = 11.2 {divided by 5}
distance upstream was 11.2
distance downstream was 11.2
Total distance = 22.4 miles
Ask the House
or
d = rt
However, the information given includes the rates and the total time of the trip.
So, solve the formula, d = rt for t (time). You'll see why in a little bit!
d = rt {distance, rate, time formula}
t = d/r {solved for t.....time equals distance divided by rate}
Now, apply that to what is given to you.
d = distance the point he got tired {which is the same distance upstream and downstream}
Remember, t = d/r {the time is the distance divided by the rate}
d/2 + d/8 = 7 {the two times are d/2 and d/8....distance divided by rate}
4d + d = 56 {multiplied entire equation by 8 to eliminate fractions}
5d = 56 {combined like terms}
d = 11.2 {divided by 5}
distance upstream was 11.2
distance downstream was 11.2
Total distance = 22.4 miles
Ask the House
