Answer:
See below.
Step-by-step explanation:
Total = 110
Let calls on third evening = x
second evening = 4x
first evening = x + 8
=> x + 4x + x + 8 = 110
=> 6x = 102
=> x = 17
First evening = x = 17 calls
Second evening = 4x = 68 calls
Third evening = x + 8 = 25 calls
Answer:
![\left[\begin{array}{cc}3&9\\5&-2\end{array}\right] +\left[\begin{array}{cc}6&0\\-8&4\end{array}\right]=\left[\begin{array}{cc}9&9\\-3&2\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D3%269%5C%5C5%26-2%5Cend%7Barray%7D%5Cright%5D%20%2B%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D6%260%5C%5C-8%264%5Cend%7Barray%7D%5Cright%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D9%269%5C%5C-3%262%5Cend%7Barray%7D%5Cright%5D)
Step-by-step explanation:
To add matrices, we add the corresponding components.
The given matrices is
![\left[\begin{array}{cc}3&9\\5&-2\end{array}\right] +\left[\begin{array}{cc}6&0\\-8&4\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D3%269%5C%5C5%26-2%5Cend%7Barray%7D%5Cright%5D%20%2B%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D6%260%5C%5C-8%264%5Cend%7Barray%7D%5Cright%5D)
We add the corresponding components to get;
![\left[\begin{array}{cc}3&9\\5&-2\end{array}\right] +\left[\begin{array}{cc}6&0\\-8&4\end{array}\right]=\left[\begin{array}{cc}3+6&9+0\\5+-8&-2+4\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D3%269%5C%5C5%26-2%5Cend%7Barray%7D%5Cright%5D%20%2B%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D6%260%5C%5C-8%264%5Cend%7Barray%7D%5Cright%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D3%2B6%269%2B0%5C%5C5%2B-8%26-2%2B4%5Cend%7Barray%7D%5Cright%5D)
We simplify to get:
Two sets (or three technically)
sets {2, 4, 6, 8, 10} & {8,9,10}
The probability of one of the above numbers because it is a union of those two vars/sets so numbers from either set go
{2, 4, 6, 8, 9, 10}
Thats 6 of the 10 numbers
6/10
.6
If i'm wrong, sorry, haven't done this kind of stuff in a while
Are you sure you wrote all the correct numbers because it does not work
