SOLUTION: A spider crawled from the picnic basket to home at an average speed of 5 feet per minute, and then crawled back the same way at an average speed of 7 feet per minute. If the round

Algebra ->  Customizable Word Problem Solvers  -> Mixtures -> SOLUTION: A spider crawled from the picnic basket to home at an average speed of 5 feet per minute, and then crawled back the same way at an average speed of 7 feet per minute. If the round       Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 1107390: A spider crawled from the picnic basket to home at an average speed of 5 feet per minute, and then crawled back the same way at an average speed of 7 feet per minute. If the round trip took 1 minute and 30 seconds, how many feet is the spider's one-way trip from the picnic basket to home?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The trip from the basket to home:
Let +d+ = the one-way distance
(1) +d+=+5%2At+
(2) +d+=+7%2A%28+1.5+-+t+%29+
-------------------------
Plug (1) into (2)
(2) +5t+=+7%2A%28+1.5+-+t+%29+
(2) +5t+=+10.5+-+7t+
(2) +12t+=+10.5+
(2) +t+=+10.5%2F12+
(2) +t+=+21%2F24+
(2) +t+=+7%2F8+
-----------------------
(1) +d+=+5t+
(1) +d+=+5%2A%28+7%2F8+%29+
(1) +d+=+35%2F8+
(1) +d+=+4+%2B+3%2F8+
and
+%283%2F8%29%2A12+=+36%2F8+
+36%2F8+=+4.5+
-----------------------
The one-way trip is 4 ft 4.5 in
--------------------------------
check:
(2) +d+=+7%2A%28+1.5+-+t+%29+
(2) +4.375+=+7%2A%28+1.5+-+.875+%29+
(2) +4.375+=+10.5+-+6.125+
(2) +4.375+=+4.375+
OK