Answer:
56.75% probability that a mechanic can complete 16 oil changes in an eight-hour day
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

What is the probability that a mechanic can complete 16 oil changes in an eight-hour day
16 oil changes in 8 hours is 2 changes per hour, that is, one each 30 minutes.
This probability is the pvalue of Z when X = 30. So



has a pvalue of 0.5675
56.75% probability that a mechanic can complete 16 oil changes in an eight-hour day
Answer:

Step-by-step explanation:
To find the surface area of a cone, one uses the following formula,

Where (r) is the radius of the base of the cone, and (h) is the height of the cone, (
) represents the numerical constant (3.1415...). In order for this formula to work, one needs the height of the cone. This can be found using the Pythagorean theorem. One can form a right triangle with the base's radius, the side length, and height of the cone, then solve for the height of the cone. The Pythagorean theorem states the following,

Substitute,

Simplify,

Inverse operations,

Now one can use the formula to find the surface area of a cone, substitute in the given values, and solve,

Substitute,


Answer:
Most stars have small amounts of heavy elements like carbon, nitrogen, oxygen and iron. But the shine from the stars comes from burning hydrogen into helium in their cores.
♀️ if this helps

in case you wonder why we used 105 as LCD,
21 = 3 * 7
15 = 3 * 5
the "3" is common to both denominators, so we "use it once" and our LCD is then 3 * 7 * 5.
Ax²+bx+c=0
The formula to solve for x is:

So for 3x²+13x+10=0, plug in the data
x=-13±√13²-4(3)(10) / 2(3)
x=-13±√169-120 / 6
x=-13±√49 /6
x=-13<span>±7 / 6
x=-13+7/6
x=-6/6
x=-1x=-13-7/ 6
x=-20/6 or 3.3repeating
3x</span>²+14x+15=0
x=-14±√14²-4(3)(15) / 2(3)
x=-14±√196-180 /6
x=-14<span>±</span>√16 / 6
x=-14+4/6
x=-10/6 or 1.6repeatingx=-14-4/6
x=-18/6
x=-3