Answer:
(A) 0.0013
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean 
and standard deviation 
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
The probability that telephone call selected a random will last more than 15.5 min is most nearly
This is 1 subtracted by the pvalue of Z when X = 15.5.
So
has a pvalue of 0.9987
1 - 0.9987 = 0.0013
So the correct answer is:
(A) 0.0013
This would be easiest to do by completing the square.
x^2+10x-2=0
x^2+10x=2
x^2+10x+25=27
(x+5)^2=27
x+5=±√27
x=-5±√27
(x+5+√27)(x+5-√27)
Answer:
The answer is 0.01, 0.1, 0.1, 0.11, 1 and 1.11
Step-by-step explanation:
Answer:
A. 30 adults; B. 24 not dolls
Step-by-step explanation:
A.
B.
If five-eighths of the prizes were dolls, then three-eighths of the prizes were not dolls.
Answer : The equation could you use to find p is, 
Step-by-step explanation :
Let the cost of 1 pen be, 'x'
and the cost of 1 pencil is, 'p'
As we are given that total cost of 1 pen and 1 pencil is $2.10. The equation will be:
............(1)
And we have also given that the pen costs twice as much as a pencil. The equation will be:
............(2)
Now put the equation 2 in equation 1, we get:
Thus, the equation could you use to find p is,
