The rates are additive: you can calculate the<em> inlet </em>rate and the <em>outlet</em> rate and add them algebraically, i.e. the inlet rate will be positive and the outlet rate will be negative.
The owner already knows that the limit for the average time delivered pizzas is 38 minutes. So we conclude
1.-The resulting mean from sample data ( x ) ( 27 customers) need to be smaller than 38 minutes, any value of sample above 38 minutes means more time for the delivery action and will indicate a failure for the future project
2.-As sample size is smaller than 30 the test has to be t-student one tail test to the left
Test hypothesis
Null hypothesis H₀ x = 38
Alternative hypothesis Hₐ x < 38
We should test at a significance level α = 0,05 (α = 5%)
If the result of the test is to accept H₀ delivery project won´t be implemented, if on the other hand, H₀ is rejected then in the condition of the alternative hypothesis we accept Hₐ the sample indicates that we have a smaller average time than 38 minutes.
The simplest fraction for is . Write the upper bound as a fraction with the same denominator:
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Hence the range for would be:
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If the denominator of is also , then the range for its numerator (call it ) would be . Apparently, no whole number could fit into this interval. The reason is that the interval is open, and the difference between the bounds is less than .
To solve this problem, consider scaling up the denominator. To make sure that the numerator of the bounds are still whole numbers, multiply both the numerator and the denominator by a whole number (for example, 2.)
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At this point, the difference between the numerators is now . That allows a number ( in this case) to fit between the bounds. However, can't be written as finite decimals.
Try multiplying the numerator and the denominator by a different number.
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It is important to note that some expressions for can be simplified. For example, because of the common factor .
1. You would find 3.5% of 120,000 which is 4,270. then add it to 120,000 which is 162,270. 2. you would multiply every number in the word problem to get the interest. That would be $402.50 which is the answer