Answer: The mean temperature for the first eight days is 6.5 degrees
Step-by-step explanation: The most important piece of clue has been given which is the mean (average) for the observed data set, which is 7 days.
Note that the formula for the mean of a data set is derived as;
Mean = ∑x / f
Where ∑x is the summation of all observed data set and f is the number of data observed, that is 7. The formula now becomes;
6 = ∑x / 7
By cross multiplication, we now have,
6 * 7 = ∑x
42 = ∑x
This means the addition of all temperature observed on the first 7 days is 42. The temperature on the eighth day is now given as 10 degrees, this means the summation of all observed data for the first eight days would become 42 + 10 which equals 52. Therefore when calculating the mean for the first eight days, ∑x is now 52. The formula for the first eight days therefore is derived as follows;
Mean = ∑x / 8
Mean = 52 / 8
Mean = 6.5
The calculations therefore show that the mean temperature for the first eight days in January is 6.5 degrees
Answer:

Step-by-step explanation:
Given:



72 is dividable by 3. It is divisible by 3 because when you add 7 and 2, you get 9. According to the tests for divisibility, if the sum of the digits is divisible by 3, then the whole number is. 9 is divisible by 3, therefore 72 is as well.
Answer:
Wait... that's my name... whatever, here is the answer XD
Step-by-step explanation:
c+9.75=20.75 is the answer :D
Cost of his ticket is $20.75