Question

are all of these correct? please check and show ALL work. im confused on the last one and dont know what the final answer should be since it says round to 1 decimal place, thanks!

-Use rounding rule!

-this is as clear as it will show up!

5. 3 PARTS Part A This stem and loal plot was created from a sample set of performance scores 0234455 000158 Reading the individual scores from the stem and allo como his grouped frequency distribution (with added columns for PartB) Create 5 classes with a class width of 14 and 30 as the lowest class limit . classes tally freq midpoints x. fola 30-45 3.5 79 1937-38 a .s © 44-57 50-5 250.5 2 550 251 71.25 ③ 58-71 UTURE 704.5 U10-15 71-75 78.5 072-85 411 0938.5 6162.25 92.5 $556.as 195062 ③86-99|1 TOTALS 25 322.5 227012100701. Part B: Determine the standard deviation for this sample. Circle the final resut X = Fixiv .44-(Mean) = 44 46.172-4088.324 15 95.5 sa - 357.8530 sample variance ! {fixi? (X) 2 = 106708.3 -163.9472 20 (5=1809) Part C The stem and leaf plot shape shows this data is somewhat normally distributod Use Empirical Rule (no score calculations) and approximate how many scores are located more than 1 standard deviations above the mean Round to one decimal place mean +5=82.85 ~83 RUCE =h29) Mean) Empirical9,95, 99.7 meon-s-U5.02 x 45 Scores scores less than 45-36+38 scores more than 83 = 85tas 63.9.83 4 X 100=16% approximately 160% of Scores are located more than I sodo above the mean approximately 4-5 scores are more than + standard deviation us

Answer 1

Parta Classes freg. it) Midpoint (Kamil Tally ) foxon 74 30 — 44 2738 255 13005 44 - 58 unt 715 46475 - 72 LHHHH 474 37 446 - 86 LH 1 — 108 i 86 8649 Ef=25 93 If.xm =1611 108 313 Part B Mean * = Sample variance st = -1 = 6444 (Efter - En. Ef) 88313 - 64.44 x 25) 25-1 187.5067 Sample so s= 1187.5067 = 113.69] Parie: Empirical rule TI S = 64.44 £ 13:69=13444—1369, 64.4747 = 156.75, 78'13 (508, 780 The scores in between i fs le (50.8, 78.17 are 51, 57, 58, 60, 62, 63, 64, 64, 65, 66, 70, 70, 70, 71,75 The number of scores is es The percentage of numbes slojes es x 100 % & 64 % The number of geares located more than 130 abour la mean i.e above 781 es 15 liegodt, 83,85,957