SOLUTION: The heights of a maple tree and a cherry tree have a ratio of 5:2. If the maple tree grew 20cm and 20cm was cut off the top of the cherry tree the ratio of their heights would be 3

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: The heights of a maple tree and a cherry tree have a ratio of 5:2. If the maple tree grew 20cm and 20cm was cut off the top of the cherry tree the ratio of their heights would be 3      Log On


   



Question 1008252: The heights of a maple tree and a cherry tree have a ratio of 5:2. If the maple tree grew 20cm and 20cm was cut off the top of the cherry tree the ratio of their heights would be 3:1. How much taller is the maple tree than the cherry tree?
** I would really appreciate it if you could write it algebraiclly, so i UNDERSTAND. THANKS!

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
The heights of a maple tree and a cherry tree have a ratio of 5:2.
If the maple tree grew 20cm and 20cm was cut off the top of the cherry tree the ratio of their heights would be 3:1.
How much taller is the maple tree than the cherry tree?
:
let x = the multiplier
then
5x = the height of the Maple tree in cm
and
2x = the height of the Cherry tree
:
"If the maple tree grew 20cm and 20cm was cut off the top of the cherry tree the ratio of their heights would be 3:1."
%28%285m%2B20%29%29%2F%28%282x-20%29%29 = 3%2F1
Cross multiply
1(5m+20) = 3(2x-20
distribute
5x + 20 = 6x - 60
basic algebra
20 + 60 = 6x - 5x
80 = x
the multiplier is is 80, therefore
5*80 = 400 cm is the height of Maple
and
2*80 = 160 cm is the height of the Cherry
:
"How much taller is the maple tree than the cherry tree?"
400 - 160 = 240 cm taller
;
:
:
Check this in the equation: %28%285m%2B20%29%29%2F%28%282x-20%29%29 = 3%2F1
%28%28400%2B20%29%29%2F%28%28160-20%29%29 = 3%2F1
420%2F140 = 3%2F1