Question

Paving stones: 174 paving stones were examined for cracks, and 16 were found to be cracked. The same 174 stones were examined for discoloration, and 21were found to be discolored. A total of 3 stones were both cracked and discolored. One of the 174 stones is selected at random. Round all answers to fourdecimal places.Part 1 of 4(a) Find the probability that it is cracked.The probability that it is cracked is 0.0919SPart 2 of 4(b) Find the probability that it is discolored.The probability that it is discolored is 0.1207Part: 2/4Part 3 of 4(c) Find the probability that it is not cracked.The probability that it is not cracked is

Answer 1

Define Given

We are given the following information:

• 174 paving stones total (examined)

,

• 16, paving stones ,cracked

,

• 21, paving stones ,discolored

,

• 3, paving stones ,both cracked and discolored

We are trying to find the probability of paving stones that are not cracked.

Solving

Since we know from our given that 16 paving stones were cracked plus an additional 3 paving stones were both cracked and discolored, the total amount of cracked stones out of the 174 paving stones is equal to 19.

Therefore, we know that there will be 155 paving stones that aren't cracked. In order to find the probability, we will need to divide this number over the total amount of stones present:

`\text{Probability of not cracked paving stones}=(155)/(174)`

If we evaluate this fraction, we should obtain our answer.

Answer

The probability that a paving stone isn't cracked is equal to 0.890805.