In: Math
AM -vs- PM Test Scores: In my AM section of statistics there are 22 students. The scores of Test 1 are given in the table below. The results are ordered lowest to highest to aid in answering the following questions.
index | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 |
score | 35 | 50 | 58 | 59 | 60 | 61 | 65 | 66 | 68 | 68 | 71 | 74 | 76 | 76 | 79 | 82 | 84 | 88 | 90 | 92 | 94 | 97 |
(a) The value of P90 ---->
(b) Complete the 5-number summary.
Minimum | = | 35 |
Q1 | = | ??? |
Q2 | = | ??? |
Q3 | = | ??? |
Maximum | = | 97 |
First the data has to be arranged in the ascending order which the data is already arranged.
a) Percentile divides the data into 100 parts.
= (k)th percentile
The formula to look for the k th percentile value =
n = 22
90th percentile =
=
=
= 92 + 0.7 (94 - 92)
= 93.4
(b) Complete the 5-number summary.
Minimum | = | 35 |
Q1 | = | |
Q2 | = | |
Q3 | = | |
Maximum | = | 97 |
Quartile divides the data into 4 parts.
=
= 5th + 0.75 (6th - 5th) value
= 60 + 0.75 (61 - 60)
= 60.75
= 11th + 0.5 (12th -11th) value
= 71 + 0.5 (74 - 71)
= 72.5
= 17th + 0.25 (18th -17th) value
= 84 + 0.25 (88 - 84)
= 85