Normal Distribution, standard units #1

How should we identify the area under the curve in the following figure?

• from 1 standard deviation to the left of the mean to the end of the curve.

• From the mean to the end of the curve.

• from 1 standard deviation to the left of the mean to the 3 standard deviations to the right of the mean.

• from the mean to 3 standard deviations to the right of the mean.

How should we identify the area under the curve in the following figure?

• From the mean to 2 standard deviations to the right.

• From 3 standard deviations to the left of the mean to 3 standard deviations to the right of the mean.

• From the mean to 2 standard deviations to the left.

• From 2 standard deviations to the left of the mean to 2 standard deviations to the right of the mean.

How should we identify the area under the curve in the following figure?

• From the beginning of the curve to the mean.

• From 3 standard deviations to the left of the mean to 1 standard deviations to the left of the mean.

• From the beginning of the curve to 1 standard deviations to the left of the mean.

• From the beginning of the curve to 1 standard deviations to the right of the mean.

What area under the curve is represented in the figure?

• 83.99%

• 84.13%

• 50%

• 97.72%

What area under the curve is represented in the figure?

• 95.44%

• 99.72%

• 68.26%

• 100%

What area under the curve is represented in the figure?

• 50%

• 47.72%

• 15.73%

• 15.87%

In average, the speed of a car in a highway is 95 km/h, with a standard deviation of 5 km/h. What percentage of cars drive between 80 km/h and 85 km/h. (Write only the number of the percentage, with 2 decimals without percentage symbol).

The mean life of a battery is 50 hours with a standard deviation of 6 hours. What is the percentage of batteries with a life longer than 56 hours. (Write only the number of the percentage, with 2 decimals without percentage symbol).

The scores of a standard test are normally distributed with a mean score of 75 and a standard deviation of 15. What's the percentage of students that will have scores between 45 and 75? (Write only the number of the percentage, with 2 decimals without percentage symbol).

A machine fills bottles in a factory. It pours, in average 477 mL inside each bottle , with a standard deviation of 6 mL. What percentage of bottles were filled with more than 483 mL? (Write only the number of the percentage, with 2 decimals without percentage symbol).