Question 1202656
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x = amount of the 9% saline solution in cubic centimeters (cc)
0.09x = amount of pure saline from the 9% solution.


Add on 70*0.17 = 11.9 more ccs of pure saline to get 0.09x+11.9 ccs of total pure saline.


Let A = 0.09x+11.9 to represent this quantity.


B = total amount of solution
B = x + 70


A/B = concentration of saline
(0.09x+11.9)/(x + 70) = 0.13



Let's solve for x
(0.09x+11.9)/(x + 70) = 0.13
0.09x+11.9 = 0.13(x + 70)
0.09x+11.9 = 0.13x + 9.1
0.09x-0.13x = 9.1-11.9
-0.04x = -2.8
x = -2.8/(-0.04)
x = 70



Answer: <font color=red>70 ccs</font> of the 9% saline solution. 
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