ok so take 4:20 pm and subtract 4 hrs from it so they left at 12: 20 pm
hope this helps :)
Solution :
Let A = Economics, B = Mathematics
n(A) = 311, n(B) = 243, ![$n(A \cap B) = 135$](https://tex.z-dn.net/?f=%24n%28A%20%5Ccap%20B%29%20%3D%20135%24)
a). So, ![$n(A \cup B) = n(A) +n(B) - n(A \cap B)$](https://tex.z-dn.net/?f=%24n%28A%20%5Ccup%20B%29%20%3D%20n%28A%29%20%2Bn%28B%29%20-%20n%28A%20%5Ccap%20B%29%24)
= 311 + 243 - 135
= 419
b). n(A only) = 311 - 135
= 176
n(B only) = 243 - 135
= 108
Exactly one of these two courses
![$=\frac{176+108}{500}$](https://tex.z-dn.net/?f=%24%3D%5Cfrac%7B176%2B108%7D%7B500%7D%24)
= 0.568
c). Neither economics nor mathematics
![$=\frac{500-419}{500} $](https://tex.z-dn.net/?f=%24%3D%5Cfrac%7B500-419%7D%7B500%7D%20%24)
![$=\frac{81}{500}$](https://tex.z-dn.net/?f=%24%3D%5Cfrac%7B81%7D%7B500%7D%24)
= 0.162
Answer:
6
/5
Step-by-step explanation:
The equation for surface area on a cube is 6 * L^2, where L is side length. Essentially, six squares of equal size
12^2=144
6 * 144=864
I hope you found this both helpful and explanatory