Answer:
a) About 12%
Step-by-step explanation:
We need to find the interest rate required to achieve her goal, so we will need to use the interest-compound formula:
Where:
PV= Present Value
i= interest rate
FV= Future Value
n= number of periods
replacing the data provided:
solving for i:
first, divide both sides by 50.000 to simplify the equation:
Take roots of both sides:
±
solve for i:
±
We get two answers, but we look for a coherent value. So we take the positive one:
≈12
Answer:
0.3085 = 30.85% probability that a randomly selected pill contains at least 500 mg of minerals
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean and standard deviation
, the z-score 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 p-value, we get the probability that the value of the measure is greater than X.
Mean 490 mg and variance of 400.
This means that
What is the probability that a randomly selected pill contains at least 500 mg of minerals?
This is 1 subtracted by the p-value of Z when X = 500. So
has a p-value of 0.6915.
1 - 0.6915 = 0.3085
0.3085 = 30.85% probability that a randomly selected pill contains at least 500 mg of minerals