8 litres (amount of 20% solution needed) and 7 litres for (amount of 50% solution needed)
<u>Step-by-step explanation:</u>
Let consider ‘x’ for 20% acid solution and (15 – x) for 50% acid solution. And so, the equation would be as below,
                           20% in x + 50% in (15 – x) = 15 litres of 34%
Convert percentage values, we get
                               0.20(x) + 0.50 (15 – x) = 15 (0.34)
                               0.20 x + 7.5 – 0.50 x = 5.1
                               -0.3 x + 7.5 = 5.1
                               0.3 x = 7.5 – 5.1
                               0.3 x = 2.4

Apply ‘x = 8’ value in (15 – x) we get,
                          15 – 8 = 7 litres
The value of 7 litres for (amount of 50% solution needed)
 
        
             
        
        
        
Answer:
x = 34
Step-by-step explanation:
Add together all three angles because together they equal 180 degrees
x + 12 + x + 100 = 180         Combine like terms
2x + 112 = 180
      - 112   - 112                   Subtract 112 from both sides
2x = 68                              Divide both sides by 2
x = 34
 
        
                    
             
        
        
        
Answer: probability =  0.506
Step-by-step explanation:
The data we have is:
Total people: 205 + 160 + 40 = 405 
prefer cats: 205
prefer dogs: 160
neither: 40
The probability that a person chosen at random prefers cats is equal to the number of people that prefer cats divided the total number of people:
p = 205/405 = 0.506
in percent form, this is 50.6%
 
        
             
        
        
        
Answer:
<u>25 students</u>
Step-by-step explanation:
20 times 5 equals 100
5 times 5 equals 25
To get to 100 students you would times it by 5 and because we times'd the 20 times 5 we need to do the same to the 5 which would result in 25 students. Hope this helped! xx
 
        
             
        
        
        
Answer:
-21n + 16
Step-by-step explanation:
Start with distributive property
-24n + 16 + 3n
Combine like terms
-21n + 16
There is a part of the equation missing so I can't solve completely