Using the normal distribution, it is found that the life span of an appliance that has a z-score of –3 is of 24 months.
<h3>Normal Probability Distribution</h3>
The z-score of a measure X of a normally distributed variable with mean
and standard deviation
is given by:

- The z-score measures how many standard deviations the measure is above or below the mean.
- Looking at the z-score table, the p-value associated with this z-score is found, which is the percentile of X.
In this problem, the parameters are given as follows:
.
Hence:


X - 48 = -24
X = 24.
The life span of an appliance that has a z-score of –3 is of 24 months.
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Answer:
Step-by-step explanation:
4
For example long division of 30 by 2 first 2 divided by 3 is 1 put it down then multiply 1 by 2 and subract then just repeat
Express √3 + i in polar form:
|√3 + i| = √((√3)² + 1²) = √4 = 2
arg(√3 + i) = arctan(1/√3) = π/6
Then
√3 + i = 2 (cos(π/6) + i sin(π/6))
By DeMoivre's theorem,
(√3 + i)³ = (2 (cos(π/6) + i sin(π/6)))³
… = 2³ (cos(3 • π/6) + i sin(3 • π/6))
… = 8 (cos(π/2) + i sin(π/2))
… = 8i
The formula to find the amount is
here A is amount
P is the principal
'r' is the rate of interest
n is the number of years.
Case 1.
Stevan invests
P =$ 20,000
r = 3% = 0.03
n = 10 years
Hence the interest earned
= A - P = 26878.33 - 20000 = $6878.33
Case 2.
Evan invests
P = $10,000
r = 7% = 0.07
n = 7 years
Hence the interest earned
= A - P = 16057.81 - 10000 = 6057.81
Difference in the interest = 6878.33 - 6057.81 = $820.52
Rounded to the nearest dollar difference in interest = $821