SOLUTION: Rip skates across a frozen lake at 10 mph. and returns at 5 mph. if his total skating time is one hour, how wide is the lake?

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: Rip skates across a frozen lake at 10 mph. and returns at 5 mph. if his total skating time is one hour, how wide is the lake?      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 136069This question is from textbook algebra structure and method
: Rip skates across a frozen lake at 10 mph. and returns at 5 mph. if his total skating time is one hour, how wide is the lake? This question is from textbook algebra structure and method

Answer by ptaylor(2198) About Me  (Show Source):
You can put this solution on YOUR website!
Distance(d) equals Rate(r) times Time(t) or d=rt; r=d/t and t=d/r
Let d=distance across the lake (or width)
Time to cross the lake=d/10
Time to return=d/5
Now we are told that the above times add up to 1 hour, so:
d/10+d/5=1 multiply each term by 10
d+2d=10
3d=10 divide each side by 3
d=3 1/3 mi----------------------width of lake
CK
(3 1/3)/10+(31/3)/5=1
3 1/3+ 6 2/3=1
1=1

Hope this helps--ptaylor