Answer:
Step-by-step explanation:
They are equivalent.  Use the distributive property.
3(x+3)
the 3 on the outside of the parenthesis is multiplied by the variable(the letter) and thenthe constant(number) inside the parenthesis.
makes and equivalent equation 3x+9
 
        
             
        
        
        
Answer:
5
Step-by-step explanation:
 When you divide 25/5 the answer is 5 dollars per store
 
        
                    
             
        
        
        
Answer:
C.
Step-by-step explanation:
10 cups divided by 4 containers  = 2.5 or 5/2 cups per 1 container
 
        
             
        
        
        
Answer:
1/4
Step-by-step explanation:
Let's denote the probabilities as following:
Probability that a teenager has a sister: 
P(A) = 12/28
Probability that a teenager has a brother: 
P(B) = 7/28
Probability that a teenager has both a sister and a brother: 
P(A⋂B) = 3/28
Probability that a selected teenager has a sister also has a brother, or in other words, he/she has a brother, given he/she had a sister:
P(B|A)
Let's apply the formula of conditional probability to work out P(B|A)
P(B|A) = P(A⋂B)/P(A) = (3/28)/(12/28) = (3*28)/(12*28) = 3/12 = 1/4
=> Option C is correct
Hope this helps!