A random sample of 10 houses in a particular area, each of which is heated with natural gas, is selected and the amount of gas (therms) used during the month of January is determined for each house. The resulting observations are 118, 125, 143, 138, 141, 122, 109, 103, 99, 90. Let μ denote the average gas usage during January by all houses in this area. Compute a point estimate of μ.

μ = 118.8

Step-by-step explanation:

Based on the data, the total number of observation is n = 10

It is known that the sample mean is the unbiased estimator of the population mean. Thus, it is suitable to use sample mean as x = μ, as the estimator of population mean,

Sample Mean x = ∑ i from 1 to n x_i/n

x = 1188/10

x = μ = 118.8

translate k to n and reflect across the line containing jk.

1. sometimes

2.   never

3   .08c = 7.50+.05c   250 pages

step-by-step explanation:

1.   sometimes

the theoretical probability of rolling a 1 is 1/6.   perhaps you got really lucky and never rolled a 1   in those 60 times.   your experimental probability is 0.   or perhaps you rolled a 1   20 times.   your experimental probability is 20/60 is 1/3.     it really just depends on how you rolled in that experiment.

2.   never

the probability of the event occurring is 1.   that is being 100 % sure it will happen.   that is the maximum amount of confidence we have.

3.   no customer card cost:   .08 times number of pages

customer card cost:   7.50 + .05 times number of pages

we want to find when it costs the same amount, so we will set these equal

let c = number of pages

.08c = 7.50+.05c

subtract .05c from each side

.08c-.05c = 7.5+.05c-.05c

.03c=7.5

divide each side by .03

.03c/.03 = 7.5/03

c =250  

the cost is the same at 250 pages