5x+6y=28,3x+2y=14----------------------------------------------------------
Answer:
0.6836
Step-by-step explanation:
(weight - mean weight) = 48
Variance, s² = 204,304
Sample size, n = 89
We need to obtain the Zscore :
Zscore = (X - mean) / standard Error
Zscore = (weight - mean weight ) / (s/√n)
s = √204304 = 452
The difference from the meanncoukdnbe either to the right or left :
Zscore = - 48 / (452/√89) OR 48 / (452/√89)
Zscore = - 48 / 47.911904 OR - 48 / 47.911904
Zscore = - 1.002 or 1.002
P(Z < - 1.002) = 0.1582 (using Z table)
P(Z < 1.002) = 0.8418
P(Z < 1.002) - P(Z < - 1.002)
0.8418 - 0.1582
= 0.6836
Answer:
The point estimate for 
is 8.5 hours.
Step-by-step explanation:
The Central Limit Theorem estabilishes that, for a random variable X, with mean and standard deviation 
, a large sample size can be approximated to a normal distribution with mean and standard deviation 
.
In this problem
We are working with a sample of 81 adults, so the point estimae of the mean is the mean number of weekly hours that U.S. adults use computers at home.
So, the point estimate for is 8.5 hours.
Answer:
2 x 6 = 12
5 x 7 = 35
12/35
Step-by-step explanation:
