The table summarizes results from 975 pedestrian deaths that were caused by automobile accidents.

| Driver Intoxicated? | Pedestrian Intoxicated? | | Yes | No | |:---:|:---:|:---:| | Yes | 51 | 74 | | No | 239 | 611 |

If one of the pedestrian deaths is randomly selected, find the probability that the pedestrian was not intoxicated or the driver was not intoxicated. Report the answer as a percent rounded to one decimal place accuracy. You need not enter the "%" symbol.

Probability = ______



Answer :

To solve this problem step-by-step:

1. Total Number of Pedestrian Deaths:
- The total number of pedestrian deaths is given as 975.

2. Number of Cases Where the Pedestrian Was Intoxicated:
- Cases where both pedestrian and driver were intoxicated: 51
- Cases where pedestrian was intoxicated, but driver was not: 239
- Total cases where pedestrian was intoxicated = 51 + 239 = 290

3. Number of Cases Where the Driver Was Intoxicated:
- Cases where both pedestrian and driver were intoxicated: 51
- Cases where driver was intoxicated, but pedestrian was not: 74
- Total cases where driver was intoxicated = 51 + 74 = 125

4. Number of Cases Where the Pedestrian Was Not Intoxicated:
- Total deaths minus cases where pedestrian was intoxicated = 975 - 290 = 685

5. Number of Cases Where the Driver Was Not Intoxicated:
- Total deaths minus cases where driver was intoxicated = 975 - 125 = 850

6. Number of Cases Where Both Pedestrian and Driver Were Not Intoxicated:
- This value is given directly as 611.

7. Number of Cases Where Either Pedestrian Was Not Intoxicated or Driver Was Not Intoxicated (or Both):
- Using the principle of inclusion and exclusion:
- Sum the number of cases where pedestrian was not intoxicated and where driver was not intoxicated, and subtract where both were not intoxicated:
- [tex]\( 685 + 850 - 611 = 924 \)[/tex]

8. Calculate the Probability:
- Probability = (Number of favorable outcomes / Total outcomes) × 100
- Probability = [tex]\( (924 / 975) \times 100 = 94.76923076923077 \)[/tex]
- Round to one decimal place: [tex]\( 94.8 \)[/tex]

Thus, the probability that the pedestrian was not intoxicated or the driver was not intoxicated is [tex]\( 94.8 \ \text{percent} \)[/tex].

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