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Question 609645: Susan Williams has been the production manager of Medical Suppliers, Inc., for the past 17 years. Medical Suppliers, Inc., is a producer of bandages and arm slings. During the past 5 years, the demand for No-Stick bandages has been fairly constant. On the average, sales have been about 87,000 packages of No-Stick. Susan has reason to believe that the distribution of No-Stick follows a normal curve, with a standard deviation of 4,000 packages. What is the probability that sales will be less than 81,000 packages?
Click here to see answer by stanbon(57219)

Question 609679: what is a scenario for 1/26 using playing cards
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Question 609707: Determining null and alternative hypotheses
A car leasing firm's records indicate that the mean number of miles driven annually in its cars has been about 14250 miles. The firm suspects that this number has decreased this past year. Suppose that the firm wishes to choose a small sample of driving distances from the past year and carry out a hypothesis test for its suspicion. State the null hypothesis Ho and the alternative hypothesis H1 that it would use for this test.

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Question 609664: find all the real zeros of F(x)=3x^4+4x^3-3x-4
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Question 609535: Hi..I try to solve this..but I got lost
At Fictional University of Technology, 65% of incoming freshmen students are male and 35% are female. Recent records indicate that 80% of entering male students will graduate with a B.Sc. degree, while 85% the female students will obtain a B.Sc. degree. If an incoming freshman student is selected at random, find
a. P(student will graduate | students is female)
b. P(student will graduate and student is female)
c. P(student will graduate)
d. If you answers in part “a” and “b” are the same, explain why. If they are different, explain why.
thx
Click here to see answer by stanbon(57219)

Question 609791: Assume that the population of heights of male college students is approximately normally distributed with mean m of 70 inches and standard deviation s of 4.15 inches. Show all work.
(A) Find the proportion of male college students whose height is greater than 68 inches.
(B) Find the proportion of male college students whose height is no more than 68 inches.
I have my work, but I want to make sure I am doing it right. We are using z score tables to determine the area(probability) based on the information given. The only thing I am really uncertain of is the on B where it is not just less than, but also = to 68 in.
Click here to see answer by stanbon(57219)

Question 609796: a carton contains 12 eggs, 5 of which are cracked. if 4 eggs are selected at random, what is the probability that exactly two of the selected eggs will be cracked

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Question 609900: The amount of monthlyt phone bill is normally distributed with a mean of $60 and a standard deviation of $12, 68% of phone bill are between $______ and $____
Click here to see answer by ewatrrr(10682)

Question 609896: the lifetime of light bulbs of a particular type are normally distributed with a mean of 370 hours and a standard deviation of 5 hours. What percentage of bulbs has lifetimes that lie within 1 standard deviation of the mean on either side?
Click here to see answer by ewatrrr(10682)

Question 609895: (1) if light bulbs have lives that are normally distributed with a mean of 2500 hours and a standard deviatin of 500 hurs, what percentage of light bulobs have a life less than 2500 hours?

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Question 609808: Find the normal approximation for the binomial probability that x = 5, where n = 14 and p = 0.5.
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Question 609807: You draw from bag 5 times, and there are 4 red and 6 black balls in the bag. what's the probability that 3 red will be drawn with no replacement?
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Question 609914: Suppose there are 3 red balls, 4 blue balls, and 5 black balls. What’s the minimum number of balls you have to draw to ensure you have at least one ball in every color?

Click here to see answer by richwmiller(9135)

Question 609930: an urn contains 5 yellow, 6 green and 7 blue balls. two balls are randomly drawn without replacement. find the probability of the following events:
A. both balls are green
B. the first ball is blue and the second is yellow
C. there is one green and one yellow ball
Click here to see answer by ewatrrr(10682)

Question 609928: the lifetime of a battery is normally distributed with a mean life of 40 hours and a standard deviation of 1.2 hours. find the probability that a randomly selected battery lasts longer than 42 hours?
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Question 609927: a basketball player makes 70% of the free throws he shoots. if he tries 13 throws what is the probability that he will make more than five throws?
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Question 609909: 5. Jane has twelve stamps worth 25 cents each and eight stamps worth 13 cents each? She selects five stamps without looking. What is the probability that she takes three of the 25 cent stamps and two of the 13 cent stamps?

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Question 609947: assume that a school district has 10,000 6th graders. in the district, the average weight of a 6th grader is 80 pounds, with a standard deviation of 20 pounds. suppose you draw a random sample of 50 students. what is the probability that the average weight of a sampled student will be between 75 and 105 pounds?
Click here to see answer by stanbon(57219)

Question 609950: a truck dispatcher for UPS sends a selivery truck to six different cities. if the truck hits all six locations in a random order, what is the prooooobability that the truck visits the cities in alphabetic order?
Click here to see answer by jim_thompson5910(28476)

Question 609949: Of 23 college sophomores at Crocodile Community College, 12 preferred pepperoni pizza, 7 preferred supreme, and 4 preferred cheese. If we picked a college sophomore at random, what is the probability that he or she would prefer cheese? Give soutionexactly in reduced fraction form.
Click here to see answer by stanbon(57219)

Question 609902: The amount of Jen's monthly phone bill is normally distributed with a mean of $50 and a standard deviatin of $10. What is the 25th percentile?
Click here to see answer by ewatrrr(10682)

Question 609953: Last fall, a gardener planted 60 iris bulbs. She found that only 45 of the bulbs bloomed in the spring. Find the empirical probability that an iris bulb of this type will bloom and how many of the bulbs should sh plant next fall if she would like at least 52 to bloom?
Click here to see answer by stanbon(57219)

Question 609955: two dice are rolled. find the probability of the following events.
A. both numbers are 4
B. the first dice fives 3 and the second gives 5
C. there is one 5 and one 6
D. one number is even and one number is odd
E. the sum is equal to 7
F. the sum is equal to 11
G. the sum is 7 or 11
H. the sum is more than 6 but less than 10
Click here to see answer by stanbon(57219)

Question 609951: A community 5k run will award $50 to the winner. 75 people enter the race, and they each pay an entry fee of $20. Assuming they are all equally likely to win, what is a fai price for the competition? Round to the nearest cent.
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Question 609948: A final exam in statistic has a mean of 73 with a standard deviation of 7.73. Random sample of 24 students is selected and the mean test score of the sample is computed. What percentage of sample means are less than 70?
Click here to see answer by stanbon(57219)

Question 609977: I have 18 letters in envelopes and stamps for 10. If one letter is selected @ random find the probability that it will be a
A) Stamped letter
B) Not a stamped letter
[In trying to solve this, there are 18 total, 10 w/stamps, therefore 8 w/o stamps. I'm not able to come up with the answers (a. 5/9 and b. 4/9) working with 10 and 8. Your direction is always appreciated. I'm sure it is simple].
Click here to see answer by jim_thompson5910(28476)

Question 609996: A child has one card numbered 1 through 9. The child places three cares in a row to form a three digit number. Find the probalitity that the number is larger than 500.
[honestly, I'm not sure where to even start with this one! Any help is appreciated!]
Click here to see answer by scott8148(6628)

Question 610021: A random sample of 33 adult men had a mean weight of 182.5 pounds and a standard deviation of
22.5 pounds. Find a 99% confidence interval for the mean weight of adult men.
Click here to see answer by ewatrrr(10682)

Question 609974: An aviary contained 12 birdies and 15 eagles. Bogey left the window open and before Paar shut it, seven of them had flown out. Find the probability that 4 birdies and 3 eagles escaped through the window in alternating order.

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Question 610031: a napa auto parts supplier wants information about how long car owners plan to keep their cars . A random sample of 41 car owners results in a mean of 7 years with a standard deviation of 3.75 years. Find the 95% confidence interval for the true population mean. Identify the point estimate for mean and margin of error
Click here to see answer by stanbon(57219)

Question 609989: I have 8 cans of soft drinks, 4 different brands with 1 regular and 1 diet for each brand. I arrange 4 cans in a row randomly. Find probability that first two are diet and second two are regular?
[I know the anser is 3/35, but I'm not sure how to get this using the combination of 2 out of 4 for regular, and 2 out of 4 for diet. Thanking you in advance for the direction!]
DCM

Click here to see answer by ewatrrr(10682)

Question 610020: A random sample of movie lengths in minutes is as follows:
110 95 131 257 118 153
8. Find the standard deviation.
9. Are any of these movie lengths considered unusual in the sense of our textbook?
Explain. Does this differ with your intuition? Explain.
Click here to see answer by stanbon(57219)

Question 610066: People were polled on how many books they read the previous year. How many subjects are needed to estimate the number of books read the previous year within one book with 99% confidence? Initial survey results indicate that the standard deviation is 14.1 books.
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Question 610074: The data below represents the amount of grams of carbohydrates in a sample serving of breakfast cereal.
10 18 24 30 19 22 24 20 18 25 20 22 19

QUESTION 12 The standard deviation for this data would be __________ grams.
Answer should be between two and four decimal places e.g. 1.23, 1.234, 1.2345 etc.
Please do NOT include units (grams) in your answer.

Click here to see answer by stanbon(57219)

Question 610069: Given belly button height (x) of students is normally distributed with a mean of 100cm and a standard deviation of 20cm. Find P(90 < x < 120).
Given that X the random variable belly button height (x) has a mean of 100 cm and standard deveiation of 20cm. Find belly button height x, such that P(belly button height [X] <=x) = 0.025.
Click here to see answer by stanbon(57219)

Question 610019: A coin is tossed 7 times. Let A be the event that the first toss is heads. Let B be the event that the fifth toss is heads.
Are A and B mutually exclusive? Why or why not?
Are A and B independent? Why or why not?
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Question 609862: three persons A,B and C speak at a function along with five other persons. If the persons speak at random, find the probability that A speaks before B and B speaks before C.
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Question 609899: How do you find expected value?
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Question 610142: A diameters of bolts produced by a certain machine ae normally distributed with a mean of 0.30 inches and a standard deviatin of 0.01 inches. What percentage of bolts will have a diameter greater than 0.32 inches?
I have: 0.32-0.30/0.01=2
Click here to see answer by nerdybill(6948)

Question 610148: Unfair coin has the probabiolity of a head is 1/4 and the probabiolity of a tails is 3/4. If tossed 32 times, how many heads do you expect to see?
I have: 16 times
Click here to see answer by ewatrrr(10682)

Question 610146: A sampole space consists of 64 separate events what are equally likely. What is the probability of each?
I have: 1/64

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Question 610145: a mean score on a standardized test is 50 with a standard deviation of 10. (a)What scores fall between -1 and +1 standard deviation? (b) What percent of all scores fall between -1 and +1 standard deviation? (c) What score falls at +2 standard deviations? (d)What percentage of scores falls between +1 and +2 standard deviation?
I have: a. 50+10=60, 50-10=40
b. 60%,40%
c. n/a
d. 40%, 30%
What did I do wrong?
Click here to see answer by ewatrrr(10682)

Question 610165: Scores on the Stanford Binet Intellengence scale have a mean of 100 and a standard deviation of 16 and are presumed to be normally distributed. A person who scores a 116 on this scale has what percentile rank within this population? Please explain.
Click here to see answer by flame8855(424)

Older solutions: 1..45, 46..90, 91..135, 136..180, 181..225, 226..270, 271..315, 316..360, 361..405, 406..450, 451..495, 496..540, 541..585, 586..630, 631..675, 676..720, 721..765, 766..810, 811..855, 856..900, 901..945, 946..990, 991..1035, 1036..1080, 1081..1125, 1126..1170, 1171..1215, 1216..1260, 1261..1305, 1306..1350, 1351..1395, 1396..1440, 1441..1485, 1486..1530, 1531..1575, 1576..1620, 1621..1665, 1666..1710, 1711..1755, 1756..1800, 1801..1845, 1846..1890, 1891..1935, 1936..1980, 1981..2025, 2026..2070, 2071..2115, 2116..2160, 2161..2205, 2206..2250, 2251..2295, 2296..2340, 2341..2385, 2386..2430, 2431..2475, 2476..2520, 2521..2565, 2566..2610, 2611..2655, 2656..2700, 2701..2745, 2746..2790, 2791..2835, 2836..2880, 2881..2925, 2926..2970, 2971..3015, 3016..3060, 3061..3105, 3106..3150, 3151..3195, 3196..3240, 3241..3285, 3286..3330, 3331..3375, 3376..3420, 3421..3465, 3466..3510, 3511..3555, 3556..3600, 3601..3645, 3646..3690, 3691..3735, 3736..3780, 3781..3825, 3826..3870, 3871..3915, 3916..3960, 3961..4005, 4006..4050, 4051..4095, 4096..4140, 4141..4185, 4186..4230, 4231..4275, 4276..4320, 4321..4365, 4366..4410, 4411..4455, 4456..4500, 4501..4545, 4546..4590, 4591..4635, 4636..4680, 4681..4725, 4726..4770, 4771..4815, 4816..4860, 4861..4905, 4906..4950, 4951..4995, 4996..5040, 5041..5085, 5086..5130, 5131..5175, 5176..5220, 5221..5265, 5266..5310, 5311..5355, 5356..5400, 5401..5445, 5446..5490, 5491..5535, 5536..5580, 5581..5625, 5626..5670, 5671..5715, 5716..5760, 5761..5805, 5806..5850, 5851..5895, 5896..5940, 5941..5985, 5986..6030, 6031..6075, 6076..6120, 6121..6165, 6166..6210, 6211..6255, 6256..6300, 6301..6345, 6346..6390, 6391..6435, 6436..6480, 6481..6525, 6526..6570, 6571..6615, 6616..6660, 6661..6705, 6706..6750, 6751..6795, 6796..6840, 6841..6885, 6886..6930, 6931..6975, 6976..7020, 7021..7065, 7066..7110, 7111..7155, 7156..7200, 7201..7245, 7246..7290, 7291..7335, 7336..7380, 7381..7425, 7426..7470, 7471..7515, 7516..7560, 7561..7605, 7606..7650, 7651..7695, 7696..7740, 7741..7785, 7786..7830, 7831..7875, 7876..7920, 7921..7965, 7966..8010, 8011..8055, 8056..8100, 8101..8145, 8146..8190, 8191..8235, 8236..8280, 8281..8325, 8326..8370, 8371..8415, 8416..8460, 8461..8505, 8506..8550, 8551..8595, 8596..8640, 8641..8685, 8686..8730, 8731..8775, 8776..8820, 8821..8865, 8866..8910, 8911..8955, 8956..9000, 9001..9045, 9046..9090, 9091..9135, 9136..9180, 9181..9225, 9226..9270, 9271..9315, 9316..9360, 9361..9405, 9406..9450, 9451..9495, 9496..9540, 9541..9585, 9586..9630, 9631..9675, 9676..9720, 9721..9765, 9766..9810, 9811..9855, 9856..9900, 9901..9945, 9946..9990, 9991..10035, 10036..10080, 10081..10125, 10126..10170, 10171..10215, 10216..10260, 10261..10305, 10306..10350, 10351..10395, 10396..10440, 10441..10485, 10486..10530, 10531..10575, 10576..10620, 10621..10665, 10666..10710, 10711..10755, 10756..10800, 10801..10845, 10846..10890, 10891..10935, 10936..10980, 10981..11025, 11026..11070, 11071..11115, 11116..11160, 11161..11205, 11206..11250, 11251..11295, 11296..11340, 11341..11385, 11386..11430, 11431..11475, 11476..11520, 11521..11565, 11566..11610, 11611..11655, 11656..11700, 11701..11745, 11746..11790, 11791..11835, 11836..11880, 11881..11925, 11926..11970, 11971..12015, 12016..12060, 12061..12105, 12106..12150, 12151..12195, 12196..12240, 12241..12285, 12286..12330, 12331..12375, 12376..12420, 12421..12465, 12466..12510, 12511..12555, 12556..12600, 12601..12645, 12646..12690, 12691..12735, 12736..12780, 12781..12825, 12826..12870, 12871..12915, 12916..12960, 12961..13005, 13006..13050, 13051..13095, 13096..13140, 13141..13185, 13186..13230, 13231..13275, 13276..13320, 13321..13365, 13366..13410, 13411..13455, 13456..13500, 13501..13545, 13546..13590, 13591..13635, 13636..13680, 13681..13725, 13726..13770, 13771..13815, 13816..13860, 13861..13905, 13906..13950, 13951..13995, 13996..14040, 14041..14085, 14086..14130, 14131..14175, 14176..14220, 14221..14265, 14266..14310, 14311..14355, 14356..14400, 14401..14445, 14446..14490, 14491..14535, 14536..14580, 14581..14625, 14626..14670, 14671..14715, 14716..14760, 14761..14805, 14806..14850, 14851..14895, 14896..14940, 14941..14985, 14986..15030, 15031..15075, 15076..15120, 15121..15165, 15166..15210, 15211..15255, 15256..15300, 15301..15345, 15346..15390, 15391..15435, 15436..15480, 15481..15525, 15526..15570, 15571..15615, 15616..15660, 15661..15705, 15706..15750, 15751..15795, 15796..15840, 15841..15885, 15886..15930, 15931..15975, 15976..16020, 16021..16065, 16066..16110, 16111..16155, 16156..16200, 16201..16245, 16246..16290, 16291..16335, 16336..16380, 16381..16425, 16426..16470, 16471..16515, 16516..16560, 16561..16605, 16606..16650, 16651..16695, 16696..16740, 16741..16785, 16786..16830, 16831..16875, 16876..16920, 16921..16965, 16966..17010, 17011..17055, 17056..17100, 17101..17145, 17146..17190, 17191..17235, 17236..17280, 17281..17325, 17326..17370, 17371..17415, 17416..17460, 17461..17505, 17506..17550, 17551..17595, 17596..17640, 17641..17685, 17686..17730, 17731..17775, 17776..17820, 17821..17865, 17866..17910, 17911..17955, 17956..18000, 18001..18045, 18046..18090, 18091..18135, 18136..18180, 18181..18225, 18226..18270, 18271..18315, 18316..18360, 18361..18405, 18406..18450, 18451..18495, 18496..18540, 18541..18585, 18586..18630, 18631..18675, 18676..18720, 18721..18765, 18766..18810, 18811..18855, 18856..18900, 18901..18945, 18946..18990, 18991..19035, 19036..19080, 19081..19125, 19126..19170, 19171..19215, 19216..19260, 19261..19305, 19306..19350, 19351..19395, 19396..19440, 19441..19485, 19486..19530, 19531..19575, 19576..19620, 19621..19665, 19666..19710, 19711..19755, 19756..19800, 19801..19845, 19846..19890, 19891..19935, 19936..19980, 19981..20025, 20026..20070, 20071..20115, 20116..20160, 20161..20205, 20206..20250, 20251..20295, 20296..20340, 20341..20385, 20386..20430, 20431..20475, 20476..20520, 20521..20565, 20566..20610, 20611..20655, 20656..20700, 20701..20745, 20746..20790, 20791..20835, 20836..20880, 20881..20925, 20926..20970, 20971..21015, 21016..21060, 21061..21105, 21106..21150, 21151..21195