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X is a normally distributed random variable with a mean of 10 and a standard deviation of 4. Find the value of X for which 70.54% of the area under the distribution curve lies to the right of it.

User Anyelina
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Answer:

To find the value of X for which 70.54% of the area under the distribution curve lies to the right of it, we need to find the z-score that corresponds to this percentile and then use it to calculate the value of X.

Let z be the z-score that corresponds to the 70.54th percentile of the standard normal distribution. We can find this z-score using a standard normal table or a calculator:

z = 0.5484

This means that 70.54% of the area under the standard normal curve lies to the left of z = 0.5484, and the remaining 29.46% of the area lies to the right of it.

We can now use the formula for standardizing a normal random variable to calculate the corresponding value of X:

z = (X - μ) / σ

where μ is the mean and σ is the standard deviation.

Rearranging this formula to solve for X, we get:

X = μ + z * σ

Substituting the values given in the problem, we get:

X = 10 + 0.5484 * 4

X = 12.1936

Therefore, the value of X for which 70.54% of the area under the distribution curve lies to the right of it is approximately 12.1936.

User Abhishek Maurya
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