Cylinder A and B area similar solid the base of cylinder has circunferencia of 4£ what’s the base if the cylinder B is 9£

d. At least 75%

Step-by-step explanation:

Since nothing is known about the distribution, we use the Chebyshev Theorem.

Chebyshev Theorem

The Chebyshev Theorem can also be applied to non-normal distribution. It states that:

At least 75% of the measures are within 2 standard deviations of the mean.

At least 89% of the measures are within 3 standard deviations of the mean.

An in general terms, the percentage of measures within k standard deviations of the mean is given by .

In this problem, we have that:

Mean = 80, standard deviation = 5.

What percentage of test-takers scored better than the trainee who scored 70?

70 = 80 - 2*5

So 70 is two standard deviations below the mean.

Due to the Chebyshev Theorem, we know that at least 75% of the measures are within 2 standard deviations of the mean, between 70 and 90, which means that this percentage is at least 75%, and the correct answer is given by option d.