Answer:
34% of lightbulb replacement requests numbering between 47 and 52
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 52
Standard deviation = 5
Between 47 and 52:
52 is the mean and 47 is one standard deviation below the mean.
By the Empirical Rule, 68% of the measures are within 1 standard deviation of the mean.
Since the normal distribution is symmetric, of those, 34% are within 1 standard deviation below the mean and the mean(47 and 52) and 34% are within the mean and one standard deviation above the mean(52 and 57).
So
34% of lightbulb replacement requests numbering between 47 and 52
Answer:
128
Step-by-step explanation:
just multiply 64 by 2..
Answer:
Lee has 19 nickels and 8 dimes
Step-by-step explanation:
hello, I think I can help you with this
Step 1
Let
value of a nickel=$0.05
value of a dime=$0.10
number of nickels=N
number of nickels=D
According to the question data Lee has $1.75 in dimes and nickels.
0.05N+0.1D=1.75,equation(1)
also, the number of nickels is 11 more than the number of dimes.mathematical speaking
N=11+D,equation(2)
Step 2
replace N from equation (2) into equation (1)
0.05N+0.1D=1.75
0.05(11+D)+0.1D=1.75
Now, solve for D
0.55+0.05D+0.1D=1.75
0.15D=1.75-0.55
D=1.2/0.15
D=8
Step 3
replace the value of D into equation(2) to obtain N
N=11+8
N=11+8
N=19
Hence, Lee has 19 nickels and 8 dimes
Have a great day.
