Hi, I'm thoroughly confused!!!!Need help to solve these.

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A pool inspector pours 2 liters of a 16% chlorine solution into 6 liters of a 20% chlorine solution. How many liters of the resulting solution must she add to 1 liters of a 30% chlorine solution to create a solution that is 24% chlorine?
2
1.4
1.2
1
0.8

Ans.1.2

A pizza company is creating a new cheese topping composed of mozzarella and cheddar. 40% of the mozzarella they selected is saturated fat. The cheddar they are adding to the topping contains no saturated fat. How many grams of cheddar must be added to every 6 grams of mozzarella to produce a topping that is 15% saturated fat?

12
9
6
10
4

Ans.10

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by Fab » Wed Jul 23, 2008 6:59 am
A pool inspector pours 2 liters of a 16% chlorine solution into 6 liters of a 20% chlorine solution. How many liters of the resulting solution must she add to 1 liters of a 30% chlorine solution to create a solution that is 24% chlorine?

Step 1:

2 lt * (0.16) = 0.32
6 lt * (0.2) = 1.2
_________________
8 lt ---------->1.52
then 1.52/8 = 0.19% (this is the chlorine solution of the resulting solution)

Step 2:

x(0.19) + 0.3 = 0.24(x+1)
0.19x + 0.3 = 0.24x + 0.24
0.06=0.05x
x=1.2

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A pizza company is creating a new cheese topping composed of mozzarella and cheddar. 40% of the mozzarella they selected is saturated fat. The cheddar they are adding to the topping contains no saturated fat. How many grams of cheddar must be added to every 6 grams of mozzarella to produce a topping that is 15% saturated fat?

6(0.4)=0.15(6+x)
2.4=0.9+0.15x
x=10

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by vivianmenon » Thu Jul 24, 2008 12:30 am
Thank you very much, Fab..you have made it so simple...i was completely confused with the sentences.

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More insight

by evansbd » Fri Aug 01, 2008 6:32 am
Depending on how fast your math skills are I did this problem similarly and found some numbers that can decrease some of the calculations shown.

2L of 16% - this is 1/4 of the solution

6L of 20% - this is 3/4 of the solution

(1/4)(16) + (3/4)(20) * these numbers are easily reduced

.04 + .15 = .19

Then we can use .19 as Fab did

.30 + .19X = .24(X+1)