Step-by-step explanation:
9 apples for $4.23
Thats the answer
Given:
Either has a school certificate or diploma or even both = 20 people
Having school certificates = 14
Having diplomas = 11
To find:
The number of people who have a school certificate only.
Solution:
Let A be the set of people who have school certificates and B be the set of people who have diplomas.
According to the given information, we have
![n(A)=14](https://tex.z-dn.net/?f=n%28A%29%3D14)
![n(B)=11](https://tex.z-dn.net/?f=n%28B%29%3D11)
![n(A\cup B)=20](https://tex.z-dn.net/?f=n%28A%5Ccup%20B%29%3D20)
We know that,
![n(A\cup B)=n(A)+n(B)-n(A\cap B)](https://tex.z-dn.net/?f=n%28A%5Ccup%20B%29%3Dn%28A%29%2Bn%28B%29-n%28A%5Ccap%20B%29)
![20=14+11-n(A\cap B)](https://tex.z-dn.net/?f=20%3D14%2B11-n%28A%5Ccap%20B%29)
![20=25-n(A\cap B)](https://tex.z-dn.net/?f=20%3D25-n%28A%5Ccap%20B%29)
Subtract both sides by 25.
![20-25=-n(A\cap B)](https://tex.z-dn.net/?f=20-25%3D-n%28A%5Ccap%20B%29)
![-5=-n(A\cap B)](https://tex.z-dn.net/?f=-5%3D-n%28A%5Ccap%20B%29)
![5=n(A\cap B)](https://tex.z-dn.net/?f=5%3Dn%28A%5Ccap%20B%29)
We need to find the number of people who have a school certificate only, i.e.
.
![n(A\cap B')=n(A)-n(A\cap B)](https://tex.z-dn.net/?f=n%28A%5Ccap%20B%27%29%3Dn%28A%29-n%28A%5Ccap%20B%29)
![n(A\cap B')=14-5](https://tex.z-dn.net/?f=n%28A%5Ccap%20B%27%29%3D14-5)
![n(A\cap B')=9](https://tex.z-dn.net/?f=n%28A%5Ccap%20B%27%29%3D9)
Therefore, 9 people have a school certificate only.
I THINK the answer is compatible numbers.............. but I'm pretty sure it is compatible numbers