Instructions for the Week of April 13

Every day you should be watching the assigned video and taking notes. When completing notes please

do so in your notebook or in a space that can be transferred to your math binder as these will be

important when we return to school. When taking notes on specific sections you are not required to do

the investigations however if you have some free time it may be fun to give them a try!

You are not required to send me your notes however all exercises must be submitted by the end of the

day two days after they were assigned. For example, Monday’s lesson is due by the end of the day

Wednesday. Thursday and Friday’s lesson is due by the end of the day Monday. These can be

submitted through turnitin by taking a picture or scanning your work and saving it as a word document

or pdf (pictures/scans should be compiled into one document to submit. This can be done by inserting

your pictures into a word document). If you are still not enrolled in our turnitin class please do so ASAP

using the following information:

Class ID: 23039930 Enrollment Key: SLMath

Collaboration is not allowed.

Collaboration: To work jointly with others or together especially in an intellectual endeavor. When

collaboration takes place, all students must demonstrate understanding of the new material.

If you have any questions throughout the week please feel free to e-mail and set up a time to discuss by

phone if necessary!

Monday- Watch Chapter 6 and 7 Review Video

Complete Survey at https://tinyurl.com/slweek2

Tuesday- Complete Chapter 6 and 7 Test Part 1

This does not need to be submitted but I encourage you to take it like a normal test (41 minutes

for the test with only your formula packet and calculator)

Wednesday- Complete Chapter 6 and 7 Test Part 2

This does not need to be submitted but I encourage you to take it like a normal test (41 minutes

for the test with only your formula packet and calculator)

Thursday- Watch Chapter 6 and 7 Test Part 1 Video

Grade your test using the mark scheme provided in the video- your graded test should be

uploaded to Turnitin

Friday- Watch Chapter 6 and 7 Test Part 2 Video

Grade your test using the mark scheme provided in the video- your graded test should be

uploaded to Turnitin

Student Name: _____________________________________ Ms. Reynolds – IBSL1 Test

Topics: Statistics Sections: Chapter 6 and 7 (Part 1)

1a. [2 marks] The following table below shows the marks scored by seven students on two different mathematics tests.

Let L1 be the regression line of x on y. The equation of the line L1 can be written in the form x = ay + b. Find the value of a and the value of b.

1b.[3 marks] Let L 2 be the regression line of y on x. The lines L1 and L2 pass through the same point with coordinates ( p , q). Find the value of p and the value of q.

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2a. [1 mark] University students were surveyed and asked how many hours, ,h they worked each month. The results are shown in the following table. Use the table to find the following values. p.

2b. [1 mark] .q

2c. [2 marks]The first five class intervals, indicated in the table, have been used to draw part of a cumulative frequency curve as shown.

2d. [2 marks]Use the cumulative frequency curve to find an estimate for the number of

students who worked at most 35 hours per month.

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3a.[2 marks] A large company surveyed 160 of its employees to find out how much time they spend traveling to work on a given day. The results of the survey are shown in the following cumulative frequency diagram. Find the median number of minutes spent traveling to work.

3b. [3 marks] Find the number of employees whose travelling time is within 15 minutes of the median.

3c. [3 marks] Only 10% of the employees spent more than minutes traveling to work. Find thek value of .k

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3d. [1 mark] The results of the survey can also be displayed on the following box-and-whisker diagram. Write down the value of .b

3e. [2 marks] Find the value of .a

3f. [2 marks] Hence, find the interquartile range.

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4a.[1 mark] The fastest recorded speeds of eight animals are shown in the following table.State whether speed is a continuous or discrete variable.

4b.[1 mark] Write down the median speed for these animals.

4c. [1 mark] Write down the range of the animal speeds.

4d.[2 marks]For these eight animals find the mean speed.

4e. [1 mark] For these eight animals write down the standard deviation.

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5a.[2 marks]A group of 10 girls recorded the number of hours they spent watching television during a particular week. Their results are summarized in the box-and-whisker plot below. The range of the data is 16. Find the value of .a

5b. [2 marks] Find the value of the interquartile range.

5c. [2 marks] The group of girls watched a total of 180 hours of television. Find the mean number of hours that the girls in this group spent watching television that week.

5d. [2 marks] A group of 20 boys also recorded the number of hours they spent watching television that same week. Their results are summarized in the table below.

Find the total number of hours the group of boys spent watching television that week.

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5e. [3 marks]Find the mean number of hours that all 30 girls and boys spent watching television that week.

5f. [2 marks] The following week, the group of boys had exams. During this exam week, the boys spent half as much time watching television compared to the previous week. For this exam week, find the mean number of hours that the group of boys spent watching television.

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6. [2 marks] A florist sells bouquets of roses. The florist recorded, in Table 1, the number of roses in each bouquet sold to customers.

Table 1

The roses can be arranged into bouquets of size small, medium or large. The data from Table 1 has been organized into a cumulative frequency table, Table 2.

Table 2

Complete the cumulative frequency table.

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Student Name: _____________________________________

Ms. Reynolds – IBSL1 Test

Topics: Statistics

Sections: Chapter 6 and 7 (Part 2)

1a. [1 mark] The histogram shows the lengths of 25 metal rods, each measured correct to the nearest cm.Write down the modal length of the rods.

1b.[3 marks] Find the median length of the rods.

1c. [1 mark] The upper quartile is 4 cm. Calculate the lower quartile.

1d. [1 mark]Calculate the interquartile range.

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2a. [1 mark] A health inspector analysed the amount of sugar in 500 different snacks prepared in various school cafeterias. The collected data are shown in the following box-and-whisker diagram. Amount of sugar per snack in grams. State what 13 represents in the given diagram.

2b.[2 marks] Write down the interquartile range for this data.

2c.[1 mark] Write down the approximate number of snacks whose amount of sugar ranges from 18 to 20 grams.

2d. [2 marks] The health inspector visits two school cafeterias. She inspects the same number of meals at each cafeteria. The data is shown in the following box-and-whisker diagrams.

Meals prepared in the school cafeterias are required to have less than 10 grams of sugar.

State, giving a reason,

which school cafeteria has

more meals that do not

meet the requirement.

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3a.[1 mark]The marks obtained by nine Mathematical Studies SL students in their projects (x) and

their final IB examination scores ( y) were recorded. These data were used to determine whether

the project mark is a good predictor of the examination score. The results are shown in the table.

Use your graphic display calculator to write down , the mean project mark.x

3b. [1 mark]Use your graphic display calculator to write down , the mean examination score.y

3c. [2 marks] Use your graphic display calculator to write down r , Pearson’s product–moment

correlation coefficient.

3d. [2 marks]The equation of the regression line y on x is y = mx + c. Find the exact value of m

and of c for these data.

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3e. [2 marks] Show that the point M ( , ) lies on the regression line y on x.x y

3f. [2 marks]A tenth student, Jerome, obtained a project mark of 17. Use the regression line y on x

to estimate Jerome’s examination score.

3g. [2 marks] Justify whether it is valid to use the regression line y on x to estimate Jerome’s

examination score.

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4a.[4 marks] A healthy human body temperature is 37.0 °C. Eight people were medically examined and the difference in their body temperature (°C), from 37.0 °C, was recorded. Their heartbeat (beats per minute) was also recorded.

Draw a scatter diagram for temperature difference from 37 °C ( ) against heartbeat ( ). Usex y a scale of 2 cm for 0.1 °C on the horizontal axis, starting with −0.3 °C. Use a scale of 1 cm for 2 heartbeats per minute on the vertical axis, starting with 60 beats per minute.

4b.[1 mark] Write down, for this set of data the mean temperature difference from 37 °C, .x

4c. [1 mark] Write down, for this set of data the mean number of heartbeats per minute, .y

4d.[2 marks]Plot and label the point M( , ) on the scatter diagram.x y

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4e.[2 marks]Use your graphic display calculator to find the Pearson’s product–moment

correlation coefficient, .r

4f. [2 marks]Hence describe the correlation between temperature difference from 37 °C and heartbeat.

4g.[2 marks] Use your graphic display calculator to find the equation of the regression line on .y x

4h. [2 marks] Draw the regression line on on the scatter diagram.y x

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