The margin of error of the random selection is 0.29
The given parameters are:
--- the sample size
--- the standard deviation
--- the mean
--- the confidence level.
The margin of error (E) is calculated as follows:
So, we have:
The z-value for 90% confidence level is 1.645.
Substitute 1.645 for z
Take square roots
Multiply
Approximate
Hence, the margin of error is 0.29
Read more about margin of error at:
Given:
Principal = $14000
Rate of interest = 10% compounded semiannually.
Time = 11 years.
To find:
The accumulated value of the given investment.
Solution:
Formula for amount or accumulated value after compound interest is:
Where, P is the principal values, r is the rate of interest in decimal, n is the number of times interest compounded in an year and t is the number of years.
Compounded semiannually means interest compounded 2 times in an years.
Putting in the above formula, we get
Therefore, the accumulated value of the given investment is $40953.65.