The caffeine content of 8-ounce cans of a certain cola drink is approximately normally distributed with mean 33 milliogram. A randomly selected 8-ounce can containing 35mg of caffeine is 1.2 standard deviations above the mean. Approximately what percent of 8-ounce cans of the cola have a caffeine content greater than 35mg?

Respuesta :

Answer:

12%

Step-by-step explanation:

Step 1

We find the standard deviation

A randomly selected 8-ounce can containing 35mg of caffeine is 1.2 standard deviations above the mean.

Mean = 33mg

35 = Mean - 1.2(standard deviation)

35 = 33 + 1.2(standard deviation)

35 - 33 = 1.2(standard deviation)

2 = 1.2(standard deviation)

Standard deviation = 2/1.2

= 1.6666666667

= 1.67

Therefore, the standard deviation is 1.67

Step 2

Using the z score formula

Z score = x - μ/σ

x = 35mg

μ = mean = 33mg

σ= standard deviation = 1.67

= 35 - 33/1.67

= 1.1976

Probabilty value from Z-Table:

P(x<35) = 0.88446

P(x>35) = 1 - P(x<35)

= 1 - 0.88446

= 0.11554

Converting to percentage = 0.11554 × 100

= 11.554%

≈ 12%

Therefore, the percent of 8-ounce cans of the cola having a caffeine content greater than 35mg is approximately 12%

Using the normal distribution, it is found that 11.5% of 8-ounce cans of the cola have a caffeine content greater than 35mg.

In a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

  • It 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, which is the percentile of X.

In this problem, a randomly selected 8-ounce can containing 35mg of caffeine is 1.2 standard deviations above the mean, which means that the z-score is Z = 1.2.

The percent of 8-ounce cans of the cola have a caffeine content greater than 35mg is 1 subtracted by the p-value of Z = 1.2, so:

Looking at the z-table, Z = 1.2 has a p-value of 0.885.

1 - 0.885 = 0.115

11.5% of 8-ounce cans of the cola have a caffeine content greater than 35mg.

A similar problem is given at https://brainly.com/question/24663213