xjinabinax88
New member
- Joined
- Sep 17, 2006
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- 1
Professor Moore who lives a few miles outside a college town records the time he takes to drive to the college each morning. Here are the times (in minutes) for 42 consecutive weekdays, with the dates in order along the rows:
8.25 7.83 8.30 8.42 8.50 8.67 8.17 9.00 9.00 8.17 7.92
9.00 8.50 9.00 7.75 7.92 8.00 8.08 8.42 8.75 8.08 9.75
8.33 7.83 7.92 8.58 7.83 8.42 7.75 7.42 6.75 7.42 8.50
8.67 10.17 8.75 8.58 8.67 9.17 9.08 8.83 8.67
a) Make a histogram of these drive times ..... (I'm got this part and graphed it...)
b) Construct an ogive for Professor Moore's drive times.
c) Use your ogive from (b) to estimate the center and 90th percentile for the distibution.
d) Use the ogive to estimate percentile corresponding to drive time 8.00 minutes.
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I got part (a) and drew the histogram. I also drew part (b) out but I'm not sure about the intervals I'm supposed to use for the x-axis of ogive graph...
(I used 6-7, 8-9, 10-11). I counted all the decimals that fall under 6-7 and recorded the frequency of that, and for the others.
However, I'm MOST confused about HOW to find percentiles from the graph and how to get the center from the graph. Please help me asap! Thank you soooo much. Appreciate it!!!!
8.25 7.83 8.30 8.42 8.50 8.67 8.17 9.00 9.00 8.17 7.92
9.00 8.50 9.00 7.75 7.92 8.00 8.08 8.42 8.75 8.08 9.75
8.33 7.83 7.92 8.58 7.83 8.42 7.75 7.42 6.75 7.42 8.50
8.67 10.17 8.75 8.58 8.67 9.17 9.08 8.83 8.67
a) Make a histogram of these drive times ..... (I'm got this part and graphed it...)
b) Construct an ogive for Professor Moore's drive times.
c) Use your ogive from (b) to estimate the center and 90th percentile for the distibution.
d) Use the ogive to estimate percentile corresponding to drive time 8.00 minutes.
---------------
I got part (a) and drew the histogram. I also drew part (b) out but I'm not sure about the intervals I'm supposed to use for the x-axis of ogive graph...
(I used 6-7, 8-9, 10-11). I counted all the decimals that fall under 6-7 and recorded the frequency of that, and for the others.
However, I'm MOST confused about HOW to find percentiles from the graph and how to get the center from the graph. Please help me asap! Thank you soooo much. Appreciate it!!!!