Answer:
.
Step-by-step explanation:
It is given that a number, x, rounded to 2 significant figures is 1300.
It is possible if,
1. The value of x is greater than of equal to 1250 and less than or equal to 1300.
i.e., ...(1)
2. The value of x is greater than of equal to 1300 and less than 1350.
i.e., ...(2)
On combining (1) and (2), we get
1350 is not included in the error interval for x.
Interval notation is .
Therefore, the error interval for x is .
Answer:
Step-by-step explanation:
In the normal distribution curve, the mean is in the middle and each line to the left and to the right of that mean represent 1- and 1+ the standard deviation. If our mean is 400, then 400 + 50 = 450; 450 + 50 = 500; 500 + 50 = 550. Going from the mean to the left, we subtract the standard deviation and 400 - 50 = 350; 350 - 50 = 300; 300 - 50 = 250. We are interested in the range that falls between 350 and 450 as a percentage. That range represents the two middle sections, each containing 34% of the data. So the total percentage of response times is 68%. We are looking then for 68% of the 144 emergency response times in town. .68(144) = 97.92 or 98 emergencies that have response times of between 350 and 450 seconds.
