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Suppose that wedding costs in the Caribbean are normally distributed with a mean of $9000 and a standard deviation of $715. Estimate the percentage of Caribbean weddings that cost:

(a) between $6855 and $11145.
(b) above $11145.
(c) below $8285.
(d) between $8285 and $11145.

1 Answer

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Final answer:

To estimate the percentage of Caribbean weddings that fall within specific cost ranges, we can use the properties of the normal distribution. Given a mean of $9000 and a standard deviation of $715, we can calculate the z-scores for the given values and use the z-table to find the corresponding probabilities. Using this approach, we can determine the percentage of Caribbean weddings that fall between specific cost ranges.

Step-by-step explanation:

To estimate the percentage of Caribbean weddings that fall within specific cost ranges, we can use the properties of the normal distribution. Given a mean of $9000 and a standard deviation of $715, we can calculate the z-scores for the given values and use the z-table to find the corresponding probabilities:

(a) To find the percentage of weddings between $6855 and $11145, we calculate the z-scores for these values: z1 = (6855 - 9000) / 715 = -3.16 and z2 = (11145 - 9000) / 715 = 1.61. Using the z-table, we find the area to the left of z1 (which corresponds to weddings below $6855) and subtract it from the area to the left of z2 (which corresponds to weddings below $11145) to find the percentage of weddings between the two values.

(b) To find the percentage of weddings above $11145, we calculate the z-score for this value: z = (11145 - 9000) / 715 = 1.61. Using the z-table, we find the area to the right of z (which corresponds to weddings above $11145).

(c) To find the percentage of weddings below $8285, we calculate the z-score for this value: z = (8285 - 9000) / 715 = -1.00. Using the z-table, we find the area to the left of z (which corresponds to weddings below $8285).

(d) To find the percentage of weddings between $8285 and $11145, we calculate the z-scores for these values: z1 = (8285 - 9000) / 715 = -1.00 and z2 = (11145 - 9000) / 715 = 1.61. Using the z-table, we find the area to the left of z1 (which corresponds to weddings below $8285) and subtract it from the area to the left of z2 (which corresponds to weddings below $11145) to find the percentage of weddings between the two values.

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