A sample of n=8 scores has a mean of m=12. What is the value of ∑x for this sample
Answer: We are given the mean of 8 scores is 12.
We are required to find the sum of these 8 observation's, 
We know that:
We are given:
Hence, sum of 8 observation's, 
Answer:
The only possible answer that is correct is the first one, x = -4.
Step-by-step explanation:
Simplify the given inequality as much as possible, and then substitute each of the given x values one by one to determine which is in the solution set.
9(2x + 1) < 9x - 18 becomes 18x + 9 < 9x - 18, which, if reduced by dividing all four terms by 9, becomes 2x + 1 < x - 2.
Simplifying further, we get x < - 3. The only possible answer that is correct is the first one, x = -4. -4 < -3 is true.
Answer:
250 cubic m
Step-by-step explanation:
volume of the Olympic grid pool
Answer:
Mean age: 48
Standard deviation: 4
Step-by-step explanation:
a) Mean
The formula for Mean = Sum of terms/ Number of terms
Number of terms
= 42 + 54 + 50 + 54 + 50 + 42 + 46 + 46 + 48+ 48/ 10
= 480/10
= 48
The mean age is 48
b) Standard deviation
The formula for Standard deviation =
√(x - Mean)²/n
Where n = number of terms
Standard deviation =
√[(42 - 48)² + (54 - 48)² + (50 - 48)² +(54 - 48)² + (50 - 48)² +(42 - 48)² + (46 - 48)² + (46 - 48)² + (48 - 48)² + (48 - 48)² / 10]
= √-6² + 6² + 2² + 6² + 2² + -6² + -2² + -2² + 0² + 0²/10
=√36 + 36 + 4 + 36 + 4 + 36 + 4 + 4 + 0 + 0/ 10
=√160/10
= √16
= 4
The standard deviation of the ages is 4
4p-13p-p=-150
-9p-p=-150
-10p=-150
<u>p=15
Order of operations. Doing so turns it into a simple division equation.</u>
