Graph has these
number of students: 8,6,4,2,1
Time(hours): 1,2,3,4,5
The graph shows the number of hours randomly selected students spent on math homework. What is the mean number of hours students spent on math homework?
A. 9 hours
B. 1.4 hours
C. 1 hour
D. 2.14
B. 1.4 hours
To find the mean, we first multiply the number of students by the time spent on math homework for each group:
(8*1) + (6*2) + (4*3) + (2*4) + (1*5) = 8 + 12 + 12 + 8 + 5 = 45
Then we divide the total by the total number of students:
45 / 21 = 1.4 hours
Therefore, the mean number of hours students spent on math homework is 1.4 hours.
For 10 consecutive days, Anthony recorded the daily high temperatures in Dayton and Laredo. The table shows the data.
Daily High Temperatures (In F)
Dayton: 77 82 85 87 90 85 79 86 91 88
Laredo: 81 79 80 86 88 92 82 88 84 87
Which city has a higher median temperature? How much higher is this city's median than the other city's median daily high temperature?
A. Laredo has a higher median daily high temperature than Dayton by 0.5 F.
B. Dayton has a higher median daily high temperature than Laredo by 0.3 F.
C. Dayton has a higher median daily high temperature than Laredo by 0.5 F.
D. Laredo has a higher median daily high temperature than Dayton by 1 F.
To find the median, we need to arrange the temperatures in ascending order first:
Dayton: 77 79 82 85 85 86 87 88 90 91
Laredo: 79 80 81 82 84 86 87 88 88 92
Since we have an even number of temperatures (10), the median is the average of the two middle values.
For Dayton, the two middle values are 85 and 86. The median for Dayton is (85 + 86) / 2 = 85.5 F.
For Laredo, the two middle values are 84 and 86. The median for Laredo is (84 + 86) / 2 = 85 F.
Therefore, Dayton has a higher median daily high temperature than Laredo by 0.5 F.
The answer is:
C. Dayton has a higher median daily high temperature than Laredo by 0.5 F.
The following data set represents the highway fuel efficiency in miles per gallon (mpg) of randomly selected cars from two car companies.
Car Company A: 35,28,35,30,31,38,35,30
Car Company B: 29,33,36,27,34,34,34,25
Which of following statements is true?
A. The cars from Company B have higher modal highway fuel efficiency than Company A.
B. The cars from Company A have higher median highway fuel efficiency than Company B.
C. The cars from Company A have a higher mean highway fuel efficiency that Company B.
D. The cars from both companies have the same mean, median, and modal highway fuel efficiency.
Calculating the mode, median, and mean for each car company:
Car Company A:
Mode: 35 (appears most frequently)
Median: (30 + 35) / 2 = 32.5
Mean: (35 + 28 + 35 + 30 + 31 + 38 + 35 + 30) / 8 = 32.375
Car Company B:
Mode: 34 (appears most frequently)
Median: (33 + 34) / 2 = 33.5
Mean: (29 + 33 + 36 + 27 + 34 + 34 + 34 + 25) / 8 = 31.75
Comparing the results:
A. The cars from Company B have higher modal highway fuel efficiency than Company A. - False
B. The cars from Company A have higher median highway fuel efficiency than Company B. - False
C. The cars from Company A have a higher mean highway fuel efficiency than Company B. - True
D. The cars from both companies have the same mean, median, and modal highway fuel efficiency. - False
Therefore, the correct statement is:
C. The cars from Company A have a higher mean highway fuel efficiency than Company B.