Answer:
Option C is correct.
Step-by-step explanation:
We have been given total 8 data
Data is : 12,15,18,20,23,23,28
Here, n=7
Median is 
Median is 20.
When one data is added n=8
The median of even number of data is

Median is
Median is 
4th terms is 20
5th terms is 23
Since, median should not be change hence,
Median will be 20.
Therefore, option C is correct.
Answer:
-7
Step-by-step explanation:
Lets assume the number Peggy is thinking of be "x".
Now as given, when twice the number is added to three times one more than the number. We can write it as
∴
--- Equation 1
Again, it is given that Peggy gets the same result as when she multiplies four times one less than the number.
∴
-- equation 2
Next, we can equate both the equation 1 and 2 as it is given that result is same.

Let´s distribute 3 into
and 4 into 
⇒ 
⇒ 
Subtract both side by 4x and 3
∴ 
∴ Peggy was thinking of -7
The answer is b. k=64 t=52.
I think It is be but idk as I am in year 7