Answer:
3.4
Step-by-step explanation:
Standard deviation of a population is defined as:
σ² = ∑(xᵢ − μ)² / n
The standard deviation of a sample is defined as:
s² = ∑(xᵢ − x)² / (n - 1)
It's not clear which one we have, so let's calculate both.
First, we must find the mean.
μ = (5+12+15+10+12+6+8+8) / 8
μ = 9.5
Now we find the squares of the differences:
(5-9.5)² + (12-9.5)² + (15-9.5)² + (10-9.5)² + (12-9.5)² + (6-9.5)² + (8-9.5)² + (8-9.5)²
= 80
Divide by n:
σ² = 80 / 8
σ² = 10
And take the square root:
σ = √10
σ ≈ 3.2
That's not one of the answers, so let's try the standard deviation of a sample instead of a population.
Instead of dividing by n, we'll divide by n-1:
s² = 80 / 7
And take the square root:
s = √(80/7)
s ≈ 3.4
So that must be it.
3 tens is 3 * 10 = 30
9 ones is 9 * 1 = 9
30 + 9 = 39
Answer: 39
Step-by-step explanation:
since the volume formula is given in the picture,
volume of the cylinder = π x 3.75^2 x 6.21 = 274.349....in^3 (this is the exact answer)
HOWEVER,
since question says round off to nearest whole number,
Volume = 3 x 4^2 x 6 = 288in^3
therefore, answer = option C.
Hope that helps.
If you like to venture further, do check out my insta <em>(learntionary)</em> where I constantly post math tips! Thanks!
Answer:
9:30 she finishes
Step-by-step explanation:
815 plus 75 is 890
there are 60 minutes in one hour
890-60 is 830
add 100 to represent another Hour
830 plus 100 is 930
9:30
therefore, it is 9:30
Answer:
I think it is the last one 4-6