2 7 Algebra Lab

“2-7 Algebra Lab Percentiles”

1. Find the median, lower quartile, and upper quartile of the scores.
Median: 16.5
Lower quartile: 10.5
Upper quartile: 23.5

2. Which performer was at the 50th percentile? the 25th percentile? the
75th percentile?
50th percentile: Arnold
25th percentile: Ingrid
75th percentile: Brooke

3. Compare and contrast the values for the median, lower quartile, upper quartile, and the scores for the 25th, 50th, and 75th percentiles.
If you estimate the percentiles, then the quartiles and the percentiles correspond. If you calculate the percentiles, Arnold is at the 50th percentile, with a scored of 17.Ingrid is at the 25th percentile, with a score of 11 and Brooke is at the 75rd percentile with a score of 25. The median of the data is 16.5, and the values for the lower and upper quartiles are 10.5 and 23.5.

4. While Victor scored at the 90th percentile, what percent of the 30 possible points did he score?
28/30=0.9333*100=93.3
About 93.3%
5. Compare and contrast the percentile rank and percent score?
The percentile rank tells where a score ranks among the rest of the scores. The percent is a comparison of a score to the highest score possible.

6. Are there any outliners in the data that could alter the results of our computations?
The data points fall between 4 and 29. There are no outliers.
No outliners

7. Deciles are values that divide a set of data into ten equal-sized parts. The 1st decile contains data up to but not including the 10th percentile; the 2nd decile contains data from the 10th decile percentile up to but not including the 20th percentile, and so on
a) Which contestants’ scores fall in the 6th decile?
Arnold and Yolanda

b) In which decile are Heather and Daniel?
4th decile