The formula for the confidence interval is given by
Sample mean + z*[σ/√n], and
Sample mean - z*[σ/√n]
We have:
Sample mean = 23.95
n = 40
σ = 2.55
z* for 99% confidence = 2.58
Substitute these values into the formula, we have
23.95 + (2.58)(2.55÷√40) = 24.99
23.95 - (2.58)(2.55÷√40) = 22.91
So the lower interval is 22.91 and the highest interval is 24.99
2x-2y
I couldn’t tell if the first figure was a one or a L or i so I solved it as a 1
Answer:
the total distance she traveled is 10 1/5
Probably 2 hours.
You can't drive 100 miles in 55 seconds, or 35 minutes, or 70 minutes (1.16 hrs.)
Hope this helps, good luck! :]