Posted by carolyn on Monday, September 15, 2008 at 11:27am.
Rachel loves to color. One of her fat crayons wears down to nothing after 15 hours and her skinny crayon wears down to nothing after 6 hours.. One day she starts coloring at 10:30am with two crayons one fat one skinny with the same height. At what time will the skinny crayon be 1/2 height of fat crayon

crayon riddle 8th grade  bobpursley, Monday, September 15, 2008 at 11:39am
The amount of crayon left is the original lengthamount used.
The amount used depends on time. Now if one assumes both were the same original length (not stated in problem), then
lengthskinny=orglengthtime*origlength/6
lengthfat=origlengthtime*origlength/15
so if lenghtskinny=1/2 lengthfat, then
1/2lengthfat=Lo(1time/6) and
lengthfat=Lo(1time/15)
I would divide the first equation by the second...
1/2= (1time/6)/(1time/15)
multiply both sides by 2(1time/15)
and it ought to solve quickly.
Nice problem: compliments to the originator.
Answer This Question
Related Questions
 linear equations  Rachel has two crayons. The fat crayon burns down to nothing ...
 linear equations  Rachel has two crayons. The fat crayon burns down to nothing ...
 Math  A jar contains 1 blue crayon, 1 green crayon, 1 black crayon, and 1 red ...
 math  Suppose that a crayon weighs the same as a marker. You have a box of ...
 Math ms sue please help!!!!!!  Simple probability You have 20 crayons to choose...
 Probability  CHECK ANSWERS  I have an eight pack of crayons. Colors red, green...
 math  a store donates 2 3/4 cases of crayons to a daycare center. each case ...
 6th grade math  Rachel completed 3/4 of her cleaning in 4 hours. How many total...
 Physics  A skier wears a jacket filled with goose down that is 15mm thick. ...
 Probability  A man has 10 ties to choose from. He wears a tie each day to work...
More Related Questions