SOLUTION: Ten percent of the reds are added to twenty percent of the blues, and the total is 24.Yet the product of the nunber of reds and 3 exceeds the number of blues by 20.How many are red

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: Ten percent of the reds are added to twenty percent of the blues, and the total is 24.Yet the product of the nunber of reds and 3 exceeds the number of blues by 20.How many are red      Log On


   



Question 95147: Ten percent of the reds are added to twenty percent of the blues, and the total is 24.Yet the product of the nunber of reds and 3 exceeds the number of blues by 20.How many are red and how many are blue?
Answer by ptaylor(2198) About Me  (Show Source):
You can put this solution on YOUR website!
Let x=number of reds
And y=number of blues
Now we are told that:
0.10x+0.20y=24-----------------------------eq1
We are also told that:
x*3=y+20 or
3x=y+20 subtract 20 from both sides
y=3x-20 -----------------------------------eq2
substitute y=3x-20 from eq2 into eq1
0.10x+0.20(3x-20)=24 get rid of parens
0.10x+0.60x-4=24 add 4 to both sides
0.10x+0.60x-4+4=24+4 collect like terms
0.70x=28 divide both sides by 0.70
x=40---------------------------------------number of reds
substitute x=40 into eq2:
y=3*40-20
y=120-20=100-------------------------------number of blue
CK
0.10*40+0.20*100=24
4+20=24
24=24
also
3*40 exceeds 100 by 20

Hope this helps--ptaylor