Answer:
$3.30
Step-by-step explanation:
15 pencils * .22 cents. = 3 dollars and 30 cents !
Answer:

--- Variance
Step-by-step explanation:
Given

Solving (a): Calculate the mean.
The given data is a grouped data. So, first we calculate the class midpoint (x)
For 51 - 58.

For 59 - 66

For 67 - 74

For 75 - 82

For 83 - 90

So, the table becomes:

The mean is then calculated as:



-- approximated
Solving (b): The sample variance:
This is calculated as:

So, we have:


-- approximated
Answer:
1680 words.
Step-by-step explanation:
There are 60 minutes in an hour. So all you need to do it 560 + 560 + 560.
I say this because he types 560 word in 20 minutes..20+20+20 is 60 so that means you have to add 560, 3 times as well.
Hope this helped! :)
What is the meaning of this question