3-2 example13

# 3-2 example13 - Student Grady Simonton Colu'se Mathll9...

This preview shows pages 1–2. Sign up to view the full content.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Student: Grady Simonton Colu'se: Mathll9: Elementaiy Statistics - Spring 3010 - CRN: 49339 Instructor: Shawn Pan-'ini - 16 weeks Date: 3.418410 Book: T1'iola: Eleinentaiy Statistics. lle Time: 11:34 AM Find the mean of the data summarized in the given frequency distribution. Compare the computed mean to the actual mean of 50.9 degrees. Low Temperature ( n F) 40 — 44 45 — 49 50 — 54 55 — 59 60 — 64 Frequency 4 8 14 6 I When working with data summarized in a frequency distribution, the exact values falling in a particular class are unknown. To make calculations possible, pretend that in each class, all sample values are equal to the class midpoint. Then use the following formula, where f is the frequency and x is the midpoint of each class. to ﬁnd the mean ofthe frequency distribution. Start by ﬁnding the class midpoints. The midpoint of two numbers is their mean. Temperature Frequency f Class Midpoint x 40—44 4 40\$42 45—49 8 47 50—54 14 52 55— 59 6 57 60— 64 1 62 Now multiply the frequencies by their midpoints. Temperature Frequencyf Class Midpoint f-x x 40 — 44 4 42 168 45 - 49 8 47 3% 50 - 54 14 52 7'28 55 — 59 6 57 342 60 - 64 1 62 62 Sum the frequency column and the f - 2; column. Page 1 Student: Grady Silnonton Colu'se: 1\-Iat11119: ElenIentaiy Statistics - Spring 3010 - C‘RN: 49339 Instructor: Shawn Pan-ini - 16 weeks Date: 3.-"'18.-"'10 Book: T1‘iola: ElenIentaiy Statistics. Me Time: 11:34 AM Temperature Frequency f Class Midpoint f- x X 40 — 44 4 42 168 45 — 49 s 47 376 50 — 54 14 52 728 55 — 59 6 57 342 60 — 64 1 62 62 Totals: 2f: 33 2 (f. x) = 1626 Substitute the sums found in the previous step into the formula to ﬁnd the mean of the data from the frequency distribution. 20%) Zr 16?6 33 a! 50.8 degrees X The computed mean and the actual mean are considered close if the difference is less than 5% of the actual mean. Otherwise the means are said to be substantially different. Page 3 ...
View Full Document

{[ snackBarMessage ]}

### Page1 / 2

3-2 example13 - Student Grady Simonton Colu'se Mathll9...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online