Response:
477
Detailed explanation:
Provided information:
Number of trials (n) = 500
Mean (m) = 0
Standard deviation (s) = 1
how many readings fall within +/- 2.000 deg F of the mean value
Mean of 0 and standard deviation of 1
P(-2 ≤ x ≤ 2)
Utilizing the Z probability calculator:
P(x ≤ 2) = 0.97725;
P(x ≤ - 2) = 0.02275
Thus:
P(x ≤ 2) - P(x ≤ - 2) = 0.97725 - 0.02275 = 0.9545
Accordingly, number of readings in 500 trials:
0.9545 multiplied by 500 equals 477.25
≈ 477 values
There are a total of 20,000 available numbers. To ascertain how many phone numbers are available, the number of digits in each number must be known. Here, I will assume each number has 7 digits. This leads to the format starting with either 373XXXX or 377XXXX, where each X can be any digit from 0 to 9. This results in 10 options for each X. Therefore, there are 10×10×10×10 = 10,000 distinct phone numbers starting with 373 and another 10,000 with 377, totaling 20,000 numbers.
