To find the probability of getting an order that is not accurate, we follow these steps:
1. Calculate the total number of orders for each restaurant by summing the accurate and not accurate orders.
- For Restaurant A:
[tex]\[
\text{Total orders from A} = 311 (\text{Accurate}) + 34 (\text{Not accurate}) = 345
\][/tex]
- For Restaurant B:
[tex]\[
\text{Total orders from B} = 264 (\text{Accurate}) + 57 (\text{Not accurate}) = 321
\][/tex]
- For Restaurant C:
[tex]\[
\text{Total orders from C} = 250 (\text{Accurate}) + 38 (\text{Not accurate}) = 288
\][/tex]
- For Restaurant D:
[tex]\[
\text{Total orders from D} = 145 (\text{Accurate}) + 10 (\text{Not accurate}) = 155
\][/tex]
2. Sum up the total number of orders across all restaurants:
[tex]\[
\text{Total orders} = 345 + 321 + 288 + 155 = 1109
\][/tex]
3. Calculate the total number of not accurate orders by summing the not accurate orders from all restaurants:
- For Restaurant A:
[tex]\[
\text{Not accurate orders from A} = 34
\][/tex]
- For Restaurant B:
[tex]\[
\text{Not accurate orders from B} = 57
\][/tex]
- For Restaurant C:
[tex]\[
\text{Not accurate orders from C} = 38
\][/tex]
- For Restaurant D:
[tex]\[
\text{Not accurate orders from D} = 10
\][/tex]
Summing these up gives:
[tex]\[
\text{Total not accurate orders} = 34 + 57 + 38 + 10 = 139
\][/tex]
4. Calculate the probability of selecting an order that is not accurate. This is found by dividing the total number of not accurate orders by the total number of orders:
[tex]\[
\text{Probability of not accurate order} = \frac{\text{Total not accurate orders}}{\text{Total orders}} = \frac{139}{1109}
\][/tex]
5. Simplify and round the probability to three decimal places:
[tex]\[
\frac{139}{1109} \approx 0.125
\][/tex]
Therefore, the probability of getting an order that is not accurate is [tex]\( \boxed{0.125} \)[/tex].
