Suppose that the duration of a particular type of criminal trial is known to be normally distributed with a mean of 22 days and a standard deviation of 6 days. 72% of all of these types of trials are completed within how many days

25.5 days

Step-by-step explanation:

Mean number of days (μ) = 22 days

Standard deviation (σ) = 6 days

Z-score for the 72nd percentile (according to tabulated values) = 0.583

The z-score for any number of days, X, is determined by:

The value of X that is greater than 72% of the trial times is:

Therefore, 72% of all of these types of trials are completed within 25.5 days.

square root

step-by-step explanation:

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.