Answer:
11) x = 21
12) x = 110
13) x = 85
14) x = 137
Step-by-step explanation:
Hope it helped <3
Answer:
x = 9
Step-by-step explanation:
set a proportion: 8/12 = 6/x => 8x = 72 => x = 9
Answer:
a is x>3
b is _> x/4 +12
c is x>-3
Step-by-step explanation: hope this helps
Answer:
Step-by-step explanation:
Complex numbers identity:
The complex numbers identity is:
Square of the sum:
In this question:
So
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%)
