Answer:
False
Step-by-step explanation:
2*2*2*2 is the correct answer
Answer:
0.0039 is the probability that the sample mean hardness for a random sample of 12 pins is at least 51.
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 50
Standard Deviation, σ = 1.3
Sample size, n = 12
We are given that the distribution of hardness of pins is a bell shaped distribution that is a normal distribution.
Formula:
Standard error due to sampling =

P(sample mean hardness for a random sample of 12 pins is at least 51)
Calculation the value from standard normal z table, we have,
0.0039 is the probability that the sample mean hardness for a random sample of 12 pins is at least 51.
Answer: it will take 2.5 hours for both people to meet after person B leaves.
Step-by-step explanation:
The distance between the house of person A and his cousin's house is 234 miles.
At the point where they meet, they would have travelled 234 miles.
Person A travelled at an average speed of 44 miles per hour.
Let t represent the time spent by Person A in travelling from his house to the point where they meet.
Distance = speed × time
Distance covered by person A would be
44 × t = 44t
One and half hours later, person B leaves his house to visit person A, travelling at an average speed of 62 miles per hour. This means that total time spent by person B in travelling to the point where they meet is (t - 0.5) hours. Distance covered would be
62(t - 0.5) = 62t - 31
Since the total distance covered is 234 miles, then
44t + 62t - 31 = 234
106t = 234 + 31 = 265
t = 265/106 = 2.5 hours