An article gave the following summary information for fracture strengths (mpa) of n = 174 ceramic bars fired in a particular kiln: x = 89.06, s = 3.22.

(a) calculate a (two-sided) confidence interval for true average fracture strength using a confidence level of 95%. (give answers accurate to 1 decimal , )does it appear that true average fracture strength has been precisely estimated? yes, this is a very narrow interval. yes, this is a very wide interval. no, this is a very narrow interval. no, this is a very wide interval.

(b) suppose the investigators had believed a priori that the population standard deviation was about 5 mpa. based on this supposition, how large a sample would have been required to estimate μ to within .5 mpa with 95% confidence? (exact answer required.)n =

third choice down

step-by-step explanation:

the first inequality is based on the number of adults and campers, and the second inequality is based on the cost of feeding both the adult and the camper.

we know that there is room for 525 people max.   it's ok to have less than 525, but it's not ok to have more than 525, so the inequality is less than or equal to.   the number combination of adults (x) and campers (y) cannot exceed this 525 max.   therefore:

x + y ≤ 525

now we talk about cost.   it costs $9 to feed one adult, so depending upon the number of adults you have (x) depends upon how much it will cost to feed that number of adults.   same with the campers, who cost $5 to feed.   the adults can be represented by 9x and the campers can be represented by 5y.   since the budget cannot exceed 1,200, the second inequality is:

9x + 5y ≤ 1200

y= -2x+4, have a great day

i want the details r