We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive pseudonymised information about your use of our website. cookie policy and privacy policy.
 
+0  
 
0
80
2
avatar

Jane needs to make 10 liters of a solution that is 10% salt. She has a solution that is 5% salt and a solution that is 25% salt. How much of each solution should Mia use?

 

Select one:

a. 4 liters of the 5% salt solution and 6 liters of the 25% salt solution

b. 2.5 liters of the 5% salt solution and 7.5 liters of the 25% salt solution

c. 7.5 liters of the 5% salt solution and 2.5 liters of the 25% salt solution

d. 8 liters of the 5% salt solution and 2 liters of the 25% salt solution

 Feb 21, 2019
 #1
avatar+18293 
+1

The total salt in the final solution has to equal the salt from the component solutions

x = liters of 25%        salt content = .25x

10-x = liters of 5 %    salt content = .05(10-x)

 

final solution salt content =  .1 (10) = 1

 

.25x+ .05(10-x) = 1

.25x + .5 - .05x = 1

.20x = .5

x = 2.5 liters of 25%       and  10 -2.5 = 7.5 liters of 5 %

 Feb 21, 2019
 #2
avatar+100439 
+2

Let the no. of liters of 5% solution= x

So...the no. of liters of 25% solution is (10 - x)

 

So.....we have this

 

5 % solution * amt +  25% solution * amt =  10% solution * 10 liters

 

.05 x + .25(10 - x) = .10 * 10   simplify

 

05x  + 2.5 - .25x +  1

 

-.20x + 2.5 = 1     subtract 2.5 from both sides

 

-.20x = - 1.5         divide both sides by .20

 

x = 7.5 liters of 5%  solution

 

And

 

10 - x =  10 - 7.5 =    2.5 liters of 25% solution

 

Answer " C "

 

 

cool cool cool

 Feb 21, 2019

19 Online Users

avatar
avatar
avatar
avatar