# The number of students in 40 schools in a certain sub-county were recorded as follows:

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The number of students in 40 schools in a certain sub-county were recorded as follows:
238  100  173  115  398  597  572  299
255  750  587  403  250  217  797  386
362  486  453  279  436  248  780  316
529  305  372  286  842  235  420  492
226  245  695  720  267  617  198  830

1. Complete the frequency distribution table below for the data.
 Number of students 100-199 200-249 250-399 400-599 600-799 800-849 Number of schools
2. draw a histogram to represent the data.

3. Use the histogram to estimate the:
• median;
• number of schools with more than 350 students.

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1.  class tally f fd cf 100-199 llll 4 0.04 4 200-249 llll l 6 0.12 10 250-399 llll llll ll 12 0.08 22 400-599 llll llll 10 0.05 32 600-799 llll l 6 0.03 38 800-849 ll 2 0.04 40

2.
• Median psn=40/2 =20th value
=10 + x × 0.08 = 20
x = 125
Median = 125+249.5
=374.5
• 49.5 × 0.08 + 10 + 6 + 2
= 21.96
≈ 22 schools