General Maths - Unit 1 Exam Revision

A consumer group conducts research to determine whether the price of a laptop is affected by its weight. They weigh 50 laptops and note each of their prices on a spreadsheet. The explanatory and response variables are, respectively:

• the 50 laptops and their prices

• the price of the laptop and the weight of the laptop

• the weight of the laptop and the price of the laptop

• the prices of the laptops and the spreadsheet

• the consumer group and the study

Which statement best describes the association between M and H?

• No association

• Non-linear association

• Negative, linear and moderate

• Positive, linear and weak

• Positive, linear and strong

Which of the following sentences is correct?

• It can be concluded that M should decrease as H increases.

• There is little evidence to show that H should increase as M increases.

• It can be concluded that M should increase as H increases.

• There is limited evidence to support that H will increase as M increases.

• There is some evidence to support that M will increase as H increases.

Which of the following scatterplots have a correlation coefficient r = 0.9218?

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• 
• 
• 
• 

A large study of Year 12 students shows that there is a negative association between the time spent doing homework each week and the time spent watching television. The correlation coefficient is r = –0.6.

From this information it can be concluded that

• the time spent doing homework is 60% lower than the time spent watching television.

• 36% of students spend more time watching television than doing homework.

• the slope of the line of best fit is 0.6.

• if a student spends less time watching television, they will do more homework.

• an increased time spent watching television is associated with a decreased time doing homework.

The equation of the least squares line of best fit for this data is wingspan = –2.99 + 0.96 × length

From this equation it can be concluded that, on average, for these aeroplanes, wingspan

• decreases by 2.03 metres with each one metre increase in length.

• increases by 0.96 metres with each one metre increase in length.

• decreases by 0.96 metres with each one metre increase in length.

• increases by 2.99 metres with each one metre increase in length.

• decreases by 2.99 metres with each one metre increase in length.

The equation of the least squares line of best fit is closest to

• y = 9.2 – 0.7x

• y = 9.2 + 0.7x

• y = 2.0 – 0.6x

• y = 2.0 – 0.7x

• y = 2.0 + 0.7x

A least squares line of best fit modelling the height (cm) of 20 children aged between 5 and 15 years was found to have the equation height = 99.97 + 2.59 × age.

The predicted height for a 14-year-old is

• 136 cm

• 136.23 cm

• 137.5 cm

• 146 cm

• 146.34 cm

A least squares line of best fit modelling the height (cm) of 20 children aged between 5 and 15 years was found to have the equation height = 99.97 + 2.59 × age.

The predicted age of a child who is 120.69 cm is

• 5

• 6

• 7

• 8

• 9

The least squares line of best fit predicts that the weight (in g) of a fish of length 30 cm would be closest to

• 240

• 252

• 262

• 274

• 310