SOLUTION: Two rainstorms occured in one week in a certain area in the first storm 30mL of rain fell per hour, and in the second storm 15 mL of rain fell per hour. Rain fell that week for a

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Two rainstorms occured in one week in a certain area in the first storm 30mL of rain fell per hour, and in the second storm 15 mL of rain fell per hour. Rain fell that week for a       Log On


   

Question 176332: Two rainstorms occured in one week in a certain area in the first storm 30mL of rain fell per hour, and in the second storm 15 mL of rain fell per hour. Rain fell that week for a total of 45 hours for a total rain fall of 975 mL how long was each storm.


Thank you
Answer by ptaylor(2198) About Me  (Show Source):
You can put this solution on YOUR website!
Let x=length of 30ml storm
then 45-x=length of the 15ml storm
Amount of rainfall for the 30ml storm=30x
Amount of rainfoall for the 15ml storm=15(45-x)
Now we know that the total amount of rainfall equals the sum of the above two amounts, so:
30x+15(45-x)=975 get rid of parens
30x+675-15x=975 subtract 675 from each side
30x-15x+675-675=975-675 collect like terms
15x=300 divide each side by 15
x=20 hr----------------------------------length of 30ml storm
45-x=45-20=25 hr------------------------------length of 15ml storm
CK
20*30+25*15=975
600+375=975
975=975
Does this help??------ptaylor