#$&* course Mth 152 Dec 1 - 4:12pm 015. ``q Query 15
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Given Solution: `aThe numbers, in order, are .1, .2, .3, .3, .4, .5, .6, .7, .8, .9, .9 The mean, obtained by adding the 11 numbers then dividing by 11, is .518. The median occurs at position (n + 1 ) / 2 = 6 in the ordered list. This number is .5. Note that there are five numbers before .5 and five numbers after .5. The maximum number of times a number repeats in this distribution is 2. So there are two modes (and we say that the distribution is bimodal). The modes are .3 and .9. ** &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& Self-critique (if necessary): okay ------------------------------------------------ Self-critique Rating: okay ********************************************* Question: `q Query problem 13.2.24 more effect from extreme value YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY Your solution: The mean is the usual average. It would definitely change. If you change the value to its correct value it will be a difference of 3 units. But the median, which is the middle number, only shifts one number to 2.39. confidence rating #$&*: 2 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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Given Solution: `aThe mean is drastically affected by the error; correcting the error changes the mean by about 3 units. The median number, however, simply shifts 1 position, changing from 2.28 to 2.39. ** &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& Self-critique (if necessary): okay ------------------------------------------------ Self-critique Rating: okay ********************************************* Question: `q Query problem 13.2.30 Salaries 6 @$19k, 8 @ 23k, 2 @ 34.5k, 7 @ 56.9k, 1 @ 145.5k. A company has 6 employees with a salary of $19,500, eight with a salary if $23,000, four with a salary of $28,300, two with a salary of $34,500, seven with a salary of $36,900, and one with a salary of $145,500. Find the mean salary for the employees (to the nearest hundred dollars) YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY Your solution: 6+8+4+2+7+1= 28 employees 19,500 * 6 = 117,000 23,000 * 8 = 184,000 28,300 * 4 = 113,200 34,500 *2 = 69000 36,900 * 7 = 258300 145,500 * 1 = 145500 887,000 / 28 = $31,700 The mode is 23,000 confidence rating #$&*: 3 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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Given Solution: `aIF THERE ARE 28 EMPLOYEES: The totals paid for each salary level are: 6 * $19,500 = $117,000 8 * $23,000 = $184,000 4 * $28,300 = $113,200 2 * $34,500 = $69,000 7 * $36,900 = $258,300 1 * $145,500 = $145,500 The grand total paid in salaries to the 28 employees is therefore $887,000, giving an average of $887,000 / 28 = $31,700. The median occurs at position (n + 1) / 2 = (28 + 1) / 2 = 14.5. Since the 14 the salary on a list ordered from least to greatest is $23,000 and the 15 th is $28300 the median is ($23000 +$28300) / 2 = $25,650. The mode is 23,000, since this salary occurs more frequently than any other. IF THERE ARE 24 EMPLOYEES: The totals paid for each salary level are: $19,000 * 6 = $114,000 $23,000 * 8 = $184,000 $34,500 * 2 = $69,000 $56,900 * 7 = $398,300 $145,500 * 1 = $145,500 Adding these gives a ‘grand total’, which is divided by the number 24 of employees to obtain the mean $37,950. The median occurs at position (n + 1) / 2 = (24 + 1) / 2 = 12.5. Since the $23000 salary covers positions 7 thru 14 in an ordered lise of salaries the median is $23,000. The mode is 23,000, since this salary occurs more frequently than any other. &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& Self-critique (if necessary): Why did you figure for 24 employees? ------------------------------------------------ Self-critique Rating: okay
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Given Solution: `aThe mean is 13.73, obtained by adding together all the numbers and dividing by n = 15. The median is in position (n+1) / 2 = (15+1)/2 = 8 on the ordered list; the 8 th number is 16. The mode is 18, which is the only number occurring as many as 3 times. ** &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& Self-critique (if necessary): Did I add the numbers wrong to not get 13.73? " Self-critique (if necessary): ------------------------------------------------ Self-critique rating: ********************************************* Question: `q Query problem 13.2.51 mean, med, mode of 0, 1, 3, 14, 14, 15, 16, 16, 17, 17, 18, 18, 18, 19, 20 YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY Your solution: The numbers are in already in order: 0, 1, 3, 14, 14, 15, 16, 16, 17, 17, 18, 18, 18, 19, 20 The mean = 206/14 = 14.71 The median is 16. The mode is 18. confidence rating #$&*: 2 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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Given Solution: `aThe mean is 13.73, obtained by adding together all the numbers and dividing by n = 15. The median is in position (n+1) / 2 = (15+1)/2 = 8 on the ordered list; the 8 th number is 16. The mode is 18, which is the only number occurring as many as 3 times. ** &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& Self-critique (if necessary): Did I add the numbers wrong to not get 13.73? " Self-critique (if necessary): ------------------------------------------------ Self-critique rating: #*&!