Answer:
a) 229 and 305 days
b) 229 days or less
c) 305 days or more
Step-by-step explanation:
The Empirical Rule(68-95-99.7 rule) states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 267
Standard deviation = 19
(a) Between what values do the lengths of the middle 95% of all pregnancies fall?_____________and___________days
By the Empirical rule, 95% of all pregnancies fall within 2 standard deviations of the mean.
So
267 - 2*19 = 229 days
to
267 + 2*19 = 305 days
(b) How short are the shortest 2.5% of all pregnancies?______days or less
95% of all pregnancies fall within 2 standard deviations of the mean. The other 5% are more than 2 standard deviations from the mean. Since the distribution is symmetric, 2.5% is more than 2 standard deviations below the mean(shortest 2.5%) and 2.5% is more than 2 standard deviations above the mean(longest 2.5%). So
267 - 2*19 = 229 days
c) How long do the longest 2.5% of pregnancies last?________days or more
Explanation in b)
267 + 2*19 = 305 days
Answer:
$57
Step-by-step explanation:
Given that:
Earnings per hour for washing cars = $9
Earnings per hour for walking dogs = $6
Number of hours for which car washing is done = 
Number of hours taken for walking dogs = 
Earnings for hours for washing cars = Per hour earnings multiplied by number of hours = $9
Earnings for hours for walking dogs = Per hour earnings multiplied by number of hours = $6
Total earnings by both = $()
Now, given that
Number of hours spent washing cars = 5 hours
Number of hours spent walking dogs = 2 hours
Therefore, total earnings by both = 9 
5 + 6 2 = <em>$57</em>
Collect like terms
-2x is the answer
Answer:
I do believe that the answer would be 56%
Step-by-step explanation:
Using estimation if the box is half full it would have 4.5 books in the box, if you add that extra book it would be around 56%
