Question 449826
The Clarke family went sailing on a lake. Their boat average 6 kilometers per hour.
 The Rourke family took their outboard runabout for a trip in the lake for the same amount of time.
 Their boat averaged 14 kilometers per hour.
 The Rourke family traveled 20 kilometers farther than the Clarke family.
 How many hours did each family spend on their boat trip?
:
let d = distance traveled by c
then
(d+20) = dist traveled by r
:
Write a time equation; time = dist/speed (travel time given as the same for both families)
:
R's time =  C's time
{{{((d+20))/14}}} = {{{d/6}}}
Cross multiply
14d = 6(d+20)
14d = 6d + 120
14d - 6d = 120
8d = 120
d = {{{120/8}}}
d = 15 mi traveled by C family
:
Find the time
15/6 = 2.5 hrs
:
Confirm the time using R family travel time
(15+20)/14 = 2.5 hrs