Answer:
A.

Step-by-step explanation:
Given
Ratio = 3:5
Q = -14
S = 2
Required
Which solution uses 
From the given parameters;



Substitute the above values in 
This gives:


<em>From the list of given options, only option A uses the given form of the formula...</em>
Answer:
The probability that the cost for someone's dog is higher than for the cat is 33.2%.
Step-by-step explanation:
With the data given, we know that the difference in cost of medical care of dogs and cats have a normal distribution with μ=-20 and σ=46.
To know the probability of the cost for the dog is higher than the cat, we have to calculate the probability of P(d>0).
Then we have to calculate z, and look up in a standarized normal distribution table.
Calculate z:

The probability of the difference being higher than 0, we have:

We can say that the probability that the cost for someone's dog is higher than for the cat is 33.2%.
To solve, you make a systems of equation:
x+(x+3)=25, the x representing the number of pigs. Since there is no multiplication and following the order of operations, you add the x’s to get 2x+3=25. Then, you subtract 3 from both sides to get 2x=22, then divide by 2 on both sides to isolate the variable. Therefore, x=11 and Mary is taking care of 11 pigs.