Answer:
the probability that the sample variance exceeds 3.10 is 0.02020 ( 2,02%)
Step-by-step explanation:
since the variance S² of the batch follows a normal distribution , then for a sample n of 20 distributions , then the random variable Z:
Z= S²*(n-1)/σ²
follows a χ² ( chi-squared) distribution with (n-1) degrees of freedom
since
S² > 3.10 , σ²= 1.75 , n= 20
thus
Z > 33.65
then from χ² distribution tables:
P(Z > 33.65) = 0.02020
therefore the probability that the sample variance exceeds 3.10 is 0.02020 ( 2,02%)
Answer:
65 degrees.
Step-by-step explanation:
It's hard to explain, but I'll try:
The outside of the first two angles is 105 and 140. Half a whole angle is 180. So, you do
180-140=40. The inside is 40.
And then 180-105=75.
Then you add the two and subtract them from 180:
40+75= 115
180-115=65
Voila!
Answer:
20/7 or 2 and 6/7
Step-by-step explanation:
This equation works out to 2/1 • 10/7, which we can easily see equals 20/7, or 2 and 6/7, by multiplying the numerators and denominators.
Look at picture for details
