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viva [34]
3 years ago
9

last week, Sara earned 84 dollars. she earned 14 dollars mowing lawns. she earned the rest of the money babysitting for 7 dollar

s per hour. how many hours (h) did she spend babysitting?
Mathematics
1 answer:
morpeh [17]3 years ago
7 0
So she earned 84 total dollars
she earned 14 dollars mowing lawns
she earned (total-mowing lawns=babysitting) 84-14=70 dollar babysitting

7 dollars per hour so
70/7=10 so
h=10
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At a financial institution, a fraud detection system identifies suspicious transactions and sends them to a specialist for revie
labwork [276]

Answer:

a. E(X) = 54.4

b. E(X) = 2.5

c. P(Y=2) = .0116

Step-by-step explanation:

a.

    E(X) = np = .40 probability * 136 trials = 54.4 blocked transmissions

    To get the expected value, we simply multiply probability times number of trials. You can look at it in simple terms by thinking if there's a 50% chance of flipping heads and you flip a coin twice, in an ideal world you will have .5*2 = 1 head.

b.

    i. Let X represent the number of suspicious transmissions reviewed until finding the first blocked one. We will use a geometric distribution to model the "first" transmission. Whenever we're looking for the "first" time something happens, we use geometric.

   ii. E(X) = 1/p , according to the geometric model.

              = 1/.4 = 2.5.

       We expect that the specialist will review 2.5 suspicious transactions <em>on average </em>before finding the first transmission that will be blocked.

c.

    i. Let Y represent the exact number of blocked transmissions out of 10. We will use a binomial distribution to model the "fixed" number of transmissions. Whenever we're looking for a "fixed" number of times something happens, we use binomial.

    ii. P(Y=k) = (n choose k)(p^k)(q^n-k)

        P(Y=2) = (¹⁰₂)(.4^2)(.6^10-2)

                    = 45 (.4^2)(.6^10-2) = .0016

        As for calculator notation, the n choose k can be accessed on a TI-84 via MATH -> PRB -> nCr. It looks like 10 nCr 2 on the display.

        Hence the probability that two transactions out of ten will be blocked is .0016 by the binomial model.

5 0
3 years ago
Which of the following shows the numbers in the box below listed in increasing order?
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Answer:

  (A) -2, 3/7, 1/2, 1.2

Step-by-step explanation:

The numbers are in increasing order when they are listed left-to-right as they appear on the number line.

The only numbers that may give you trouble are 3/7 = 6/14 and 1/2 = 7/14.

The negative number is less than any positive number. 1.2 is greater than any fraction that is less than 1.

The correct ordering is found in choice A.

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2 years ago
Which equation goes with the table?​
Andreyy89

Answer:

y=3x that is the answer

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spayn [35]
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4 years ago
You pack sandwiches for a hike with your friends. Each sandwich takes 2 slices of bread, and each hiker eats one sandwich.
Citrus2011 [14]

<u>Given</u><u> </u><u>that</u><u>:</u><u>-</u>

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→ 1 hiker = 1 sandwich.

→ Then we have to find number of bread slices for n hikers .

→ Number of bread slices for 1 hiker = 2

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