121 is big enough to assume normality and not worry about the t distribution. By the 68-95-99.7 rule a 95% confidence interval includes plus or minus two standard deviations. So 95% of the cars will be in the mph range
The question is a bit vague, but it seems we're being asked for the 95% confidence interval on the average of 121 cars. The 121 is a hint of course.
The standard deviation of the average is in general the standard deviation of the individual samples divided by the square root of n:
So repeating our experiment of taking the average 121 cars over and over, we expect 95% of the averages to be in the mph range
That's probably the answer they're looking for.
3 is in the tens and 1 is in the ones. To explain more easily... 30+1 is 31.<span />
Answer:the company bought 12 computers and 4 printers.
Step-by-step explanation:
Let x represent the number of computers that the company bought.
Let y represent the number of printers that the company bought.
The company buys a total of 16 machines. It means that
x + y = 16
Each computer costs $550 and each printer costs $390. If the company spends $8160 for all the computers and printers that was bought, it means that
550x + 390y = 8160 - - - - - - - - - - 1
Substituting x = 16 - y into equation 1, it becomes
550(16 - y) + 390y = 8160
8800 - 550y + 390y = 8160
- 550y + 390y = 8160 - 8800
- 160y = - 640
y = - 640/ - 160
y = 4
Substituting y = 4 into x = 16 - y, it becomes
x = 16 - 4
x = 12
Answer:
Step-by-step explanation:
put it on a coorinate grid,
circle circumference = 2*pi*r = 100.53
so the arc 19.2/100.53 = about 0.15 times the circumference of the circle
0.15*2pi = angle AOB in radians = 0.97
length DE is like 7.44
angle DOE is approx 0.485 radians beacuse it's half of angle AOB
area of shaded region is 804.2477 probably. I'm not sure about this last one sorry I think my calculator messed up
