# statistics

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1. The time required to complete a project is normally distributed with a mean of 80 weeks and a standard deviation of 10 weeks. The construction company must pay a penalty if the project is not finished by the dues date of the contract. If a construction company bidding on this contract wishes to be 90 percent sure of finishing by the due date, what due date (project week #) should be negotiated?

• statistics -

Use z-scores.

Formula:
z = (x - mean)/sd

You are looking to solve for x, so fill in the rest of the formula with what you know.

Find z using z-table (problem gives you percentage). Mean = 80 and standard deviation = 10.

I hope this will help get you started.

• statistics -

88.1594

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