(Sec. 12.1) Suppose that the expected cost (yy dollars) of a production run is related to the size of the run (xx units) by the equation y=4000+10xy=4000+10x. Let YY denote an observation on the cost of a run. Also, suppose size and cost are related according to a simple linear regression model. a) What is the expected cost when the size of the run is 150 units? b) By how much do you expect the cost to increase if the size of the run is increased by 10 units? c) Suppose that the standard deviation of the random error ϵϵ is $250. What is the probability that the cost of a production run of 150 units will cost more than $6000? d) Suppose the cost is recorded from a production run of 200 units, and then is also recorded from a different production run of 250 units. What is the probability that the cost of the second production run exceeds the cost of the first by more than $1500?

for b its (t) and c its (d)

step-by-step explanation:

11

step-by-step explanation:

32.50-7.50=25

225/25=11

the answer is 99.

if gloria has "carry over" minutes, (that is, any minutes paid for but not used in a month can be applied to her payment for minutes in the next month,) her total usage for the three months is: total minutes = 320 + 243 + 489 = 1052 minutes number of 200 minute blocks = 1052/200 = 5 r52 (that is 5 with a remainder of 52) rounding up the number of 200 minute blocks gives her usage for the three months as 6 blocks. the cost for six blocks is 6 x $25 = $150 she also has 200 - 52 or 148 carry over minutes if gloria pays each month and unused minutes are lost, applying the rounding up procedure to each month gives: first month usage of 320 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 second month usage of 243 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 third month usage of 489 minutes rounds up to 3 blocks of 200 minutes for a payment of 3 x $25 = $75 total payments for the three months are $50 + $50 + $75 = $175 get the plan with carry over minutes!