Posted by dawn on Monday, March 21, 2011 at 10:12pm.
to save fuel on the 240 km trip to the cottage, the Nakamura family reduce their usual average speed by 20 km/h. this lengthens their journey by 1 hour. what is the slower average speed?
pleassee help! thanks :)

math  incomplete  Ms. Sue, Monday, March 21, 2011 at 10:18pm
How long does it usually take them to make this trip?

math  dawn, Monday, March 21, 2011 at 10:53pm
oh my gosh! so my teacher handed us two versions of this question...i didn't have that answer! sorry. the proper question i will repost.

math  dawn, Monday, March 21, 2011 at 10:58pm
never mind it does not say. does this mean the question is complete and unable to answer? its a question on an assignment and i do not know how to answer it. should ijust say uncomplete?

math  drwls, Tuesday, March 22, 2011 at 5:55am
Let V1 = the original average speed and V2 = the slower average speed. You have these two equations in two unknowns:
V1  V2 = 20 (km/h)
240/V2  240/V1 = 1 (hour)
You want to solve for V2. Use substitution, V1 = V2 + 20
240/V2 240/(V2 +20) = 1
240*[1/V2  1/(V2+20)] = 1
20/[V2(V2+20)] = 1/240
V2*(V2+20) = 4800
You can solve this as a quadratic equation and take the positive root. You should get
V2 = 60 km/h

math (not incomplete)  drwls, Tuesday, March 22, 2011 at 10:32am
Note that there was enough information provided to solve for both velocities, using simultaneous equations.

math  Anonymous, Thursday, April 14, 2011 at 9:06pm
thh

math  Anonymous, Thursday, April 14, 2011 at 9:06pm
I LOVE MATH

math  Rick Ross, Tuesday, December 2, 2014 at 7:20pm
While this gave me the answer, I was unable to understand how this was done. 2/10 would not math again

math  Rick Ross, Tuesday, December 2, 2014 at 7:22pm
Also, shout out to my pears
Answer This Question
Related Questions
 math...?  to save fuel on the 240 km trip to the cottage, the Nakamura family ...
 Math  A motorist makes a journey of 240 km from Singapore to Malacca to visit ...
 MATH  Hello! I am trying to finish a math assignment. it was a bunch of math ...
 MATH  Hello! I am trying to finish a math assignment. it was a bunch of math ...
 Pre Calc  A bus trip of 90 miles would have taken an hour less if the usual ...
 Physics  Help I don't understand how to do this homework question, we didn't go...
 Math  On a trip of d miles to another city, a truck driver's average speed was ...
 College Algebra  A truck driver traveled at an average speed of 55 miles per ...
 math  a truck driver traveled at an average speed of 48 miles per hour on a 100...
 physics  a man drives with an average speed of 25 mph for 20 minutes. he rests ...
More Related Questions