1 minute = 0.25km
Step-by-step explanation:
divide both numbers that were given by 8. 8÷8 is 1 and 2÷8 is 0.25.
X+3-2x+5=10
+2x +2x
3x+ 3 + 5 = 10
-3 -3
3x + 5 = 7
-5 -5
3x=2
x=1.5
I hope all is well, and I helped! (: Good luck, rockstar!
Answer:
i think it might be d
Step-by-step explanation:
Answer : 12.56 inches²
Explanation :
Diameter is twice the radius.
Radius = 4 ÷ 2 = 2 inches
Area = 3.14r² = 3.14 × 2² = 12.56 inches²
Answer:
See the proof below.
Step-by-step explanation:
For this case we just need to apply properties of expected value. We know that the estimator is given by:

And we want to proof that 
So we can begin with this:

And we can distribute the expected value into the temrs like this:

And we know that the expected value for the estimator of the variance s is
, or in other way
so if we apply this property here we have:

And we know that
so using this we can take common factor like this:

And then we see that the pooled variance is an unbiased estimator for the population variance when we have two population with the same variance.