The nurse is using Deductive reasoning.
Deductive reasoning is a valid form of proof. Here, a person makes conclusions based on previously known facts. It is process of reasoning from one or more statements to reach a logically certain conclusion. If all the parameters are true and the terms are clear then the conclusion reached is necessarily true.

Chance of boy: 627/1,358
Chance of girl: 731/1,358
If you have a problem like:
4x+2y=20
2x+2y=16
You would subtract
4x-2y=20
-2x+2y=16
You would get the new problum
2x=4
You now want to divide the 2 on both sides to solve for x
x=2
Now that you've solved for X you want to solve for y. So use substitution to solve for y. You would want to substatute the x for the 2 in either of the problums. I'll use the first one.
4(2)+2y=20
You first want to multiply te 4(2) you would get a new problum.
8+2y=20
Now you want to subtract the 8 on both sides.
2y=12
The last step to solve for y is to divide the 2 on both sides.
Y=6
So your answers would be
x=2
y=6
Answer:
<h3>
b=
</h3>
Step-by-step explanation:
4b+5=t
First, you must get the variable alone! Substract 5 from both sides!
4b<u>+5=t </u>
-5 -5
The 5 cancels out because 5-5=0
The new equation is 4b=t-5
You must divide by 4 to get the variable alone since your solving for b!
<u>4b=t-5</u>
4 4
b= 
This is your answer!