Copy and complete the tables below by calculating the class boundaries and the midpoint for each class.
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Question No. 2
Is it possible to have a data set for which the variance and standard deviation are negative? Give a reason for your answer.
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Question No. 3
For each of the following data sets, calculate the mean, median, mode and range.
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Question No. 4
A florist is delivering bunches of mixed flowers. Summarise this data in a frequency table and use your frequency table to calculate:
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Question No. 5
An English teacher challenged her class to read at least five books over the school holidays. Summarise this data in a frequency table and use your frequency table to calculate:
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Question No. 6
Copy and complete the table below by first calculating the mean and then calculating the deviation of each data value from the mean.
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Question No. 7
Given the following data set: {6, 0, −3, 1, 5, 4, −4, 3}.
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Question No. 8
A game warden recorded the number of baboons that she saw on ten successive days: 29, 14, 17, 25, 37, 16, 23, 28, 40, 31.
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Question No. 9
Copy and complete the table below, then calculate the variance of this data.
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Question No. 10
Given: the data set {2, 4, 6, 8, 10, 12}.
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Question No. 11
Given: the data set {−12, −7, −2, 0, 3, 6, 9, 10, 14, 28}.
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Question No. 12
Ten SS2 students were asked to make a note of the number of movies that they watched at the cinema during a given month. Their responses are listed below: 2, 4, 9, 0, 6, 3, 2, 1, 5, 0. Calculate the variance of this data. Show all your calculations.
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Question No. 13
Calculate the standard deviation, correct to two decimal places, if the variance is:
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Question No. 14
Calculate the variance, correct to two decimal places, if the standard deviation is:
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Question No. 15
Calculate the standard deviation of the following data sets. Write your answers in simplified surd form.
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Question No. 16
Refer to your answers to question 3. What do you notice about the standard deviations of the following pairs of sets?
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Question No. 17
Is it possible to have a data set for which the variance and standard deviation are zero? Give a reason for your answer.
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Question No. 18
Use the same data as in the previous example on the temperature of cooled water. Summarise the data in a frequency table using the classes (−17, −13], (−12, −8], and so on.
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Question No. 19
The number of meals served daily at a school cafeteria over a period of 40 school days was as follows. Summarise this data in a frequency table using the classes 91−100, 101−110, and so on.
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Question No. 20
The masses of 56 papayas (in grams) were as follows. Summarise this data in a frequency table using the classes 700−799, 800−899, and so on.
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Question No. 21
The distances that some students travel every morning to get to school are as follows.
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Question No. 22
A speed trap was set on an open road where the speed limit was 80 km/h. Several motorists were caught exceeding the speed limit. The speeds at which these motorists were travelling are shown in the table.
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Question No. 23
Copy and complete the table below.
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Question No. 24
Copy and complete the table below, by calculating:
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Question No. 25
120 students sold raffle tickets to raise funds for a new piano for the school hall. Their ticket sales are summarised in the frequency table below.
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Question No. 26
Copy and complete the table below, then estimate:
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Question No. 27
Given the following frequency table, estimate:
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Question No. 28
A class of SS2 students estimated the area (cm²) of their textbook covers. Their answers are summarised in the table below. Estimate:
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Question No. 29
A class of 45 SS2 students wrote a Science test. Their marks out of 40 are listed below. The mean of these marks is 22.6 and the standard deviation is 6.45 (correct to two decimal places).
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Question No. 30
Volunteers worked at a polling station in two-hour shifts from 6 am to 6 pm. The numbers of voters (rounded to the nearest 100) who voted during each shift are shown in the table below.
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Question No. 31
The masses of eight dogs that were weighed at an animal shelter were as follows: 5 kg, 10 kg, 12 kg, 18 kg, 21 kg, 28 kg, 40 kg and 54 kg.
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Question No. 32
A class of Primary School Mathematics students worked in groups of five as they measured the same angle and compared their measurements.
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Question No. 33
Say whether or not each of the following sets of data is suitable for representation in a histogram. Give a reason each time.
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Question No. 34
The masses and heights of some Nigerian dwarf goats are summarised in the tables below.
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Question No. 35
A small village has a population of 500 people. Their ages are given in this frequency table. Copy and complete the table by calculating the cumulative frequencies.
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Question No. 36
Draw up a new cumulative frequency table for the data in question 1, but use these class intervals: 0−20, 21−40, and so on.
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Question No. 37
Copy and complete the table and represent the cumulative frequencies in an ogive.
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Question No. 38
Students were asked to collect items to bring to school for recycling. The ogive below shows the results of this recycling effort.
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Question No. 39
The manager of a large taxi company analysed the distances that his taxis covered during one week. He presented his data in the ogive below.
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Question No. 40
Use the ogive from the previous example to answer the following questions.
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Question No. 41
For a project on Statistics, a student interviewed 160 students in her school to find out how long it took them on average to get to school every morning. She rounded the answers off to the nearest minute and presented her data in this ogive.