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:
See below ~
Step-by-step explanation:
Given :
<u>QRSTU ~ FGCDE</u>
Finding the scale factor :
- Take two corresponding sides in proportion
- RS : GC
- 40 : 12
- <u>10 : 3</u>
Applying the scale factor to find the missing sides :
- FG :
- QR : FG = 10 : 3
- 30/FG = 10/3
- FG = 30/10 x 3
- FG = 3 x 3
- <u>FG = 9</u>
- CD :
- ST : CD = 10 : 3
- 40/CD = 10/3
- CD = 40/10 x 3
- CD = 4 x 3
- <u>CD = 12</u>
- EF :
- UQ : EF = 10 : 3
- 30/EF = 10/3
- EF = 30/10 x 3
- EF = 3 x 3
- <u>EF = 9</u>
That is 30/80 that reduces down to 3/8
How u get it is 2 times 15 over 5 times 16 then divide 30 and 80 by 10 to get 3/8
Answer:
the answer would be 5
Step-by-step explanation:
:3
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