Apps. and Interpretation for IBDP Maths Ebook 1 | Page 338

Your Practice Set – Applications and Interpretation for IBDP Mathematics
(b) Use the regression line to estimate the monthly honey production from a hive that
has 700 bees, giving your answer to the nearest 0.1 kg.
[3]
Starting from 1 January 2018, the monthly honey production from the hive in (b)
increased by 2% each month.
(c) Calculate the monthly honey production from the hive after 1 year.
[4]
Yuto will sell the hive to another farm when its monthly honey production reaches 3 kg.
(d)
Find the year when Yuto sells the hive.
[4]
2. A farm food supplier monitors the number of chickens kept x against the monthly
consumption of chicken food ( y kg). The data for seven small farms on 1 July 2018 is
shown in the following table.
Number of chickens ( x ) 10 12 14 17 19 21 25
Monthly consumption ( y kg) 32 40 38 50 58 58 71
The relationship between the variables is modelled by the regression line with equation
y �ax � b .
(a) (i) Find the correlation coefficient.
(ii) Write down the exact value of a and of b .
[4]
(b) Use the regression line to estimate the monthly consumption of chicken food
when there are 24 chickens in a farm, giving your answer to the nearest kg.
[3]
Starting from 1 July 2018, the monthly consumption of chicken food from the farm in (b)
increased by 5% each month.
(c) Calculate the monthly consumption of chicken food from the farm after half a
year.
[4]
The supplier will enlarge the size of the farm when its monthly honey production reaches
100 kg.
(d)
Find the year and the month when the supplier enlarges the size of the farm.
[4]
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