CAEC Science Preparation Course: Inquiry: tables, graphs and trends

1. Vraag 1 van 16

   Which type of graph is best for showing how a city's average temperature changes month by month over a year?

   • AA map with no numbers
   • BA pictograph of the city
   • CA line graph
   • DA circle (pie) graph
   Toon antwoord

   Antwoord: C. A line graph

   Line graphs show how a value changes over time.

2. Vraag 2 van 16

   Which type of graph is best for showing what fraction of a household's garbage is food, paper, plastic and other waste?

   • AA timeline of collection days
   • BA line graph over the months
   • CA circle (pie) graph
   • DA scatter plot of two variables
   Toon antwoord

   Antwoord: C. A circle (pie) graph

   A circle graph shows how parts make up a whole, like the share of each type of waste.

3. Vraag 3 van 16

   A student graphs how the amount of water given to plants affects their height. Which variable usually goes on the horizontal (x) axis?

   • AThe height of each plant, which is what gets measured
   • BThe amount of water
   • CThe date the graph was drawn and handed in to the teacher
   • DThe name or number of each plant written in a list
   Toon antwoord

   Antwoord: B. The amount of water

   By convention, the independent variable goes on the x-axis and the dependent variable on the y-axis.

4. Vraag 4 van 16

   By how many degrees does the water temperature rise each minute?

   Time (min)	Water temperature (°C)
   0	20
   1	26
   2	32
   3	38
   4	44
   5	50

   • A6 °C
   • B20 °C
   • C5 °C
   • D10 °C
   Toon antwoord

   Antwoord: A. 6 °C

   Each minute the temperature goes up by the same amount: 26 − 20 = 6 °C, 32 − 26 = 6 °C, and so on.

5. Vraag 5 van 16

   Use the table to estimate the water temperature at 2.5 minutes.

   Time (min)	Water temperature (°C)
   0	20
   1	26
   2	32
   3	38
   4	44
   5	50

   • A35 °C
   • B25 °C
   • C32 °C
   • D38 °C
   Toon antwoord

   Antwoord: A. 35 °C

   2.5 minutes is halfway between 2 min (32 °C) and 3 min (38 °C), so the estimate is halfway: 35 °C.

6. Vraag 6 van 16

   If the pattern continues, what will the water temperature be at 7 minutes?

   Time (min)	Water temperature (°C)
   0	20
   1	26
   2	32
   3	38
   4	44
   5	50

   • A62 °C
   • B70 °C
   • C56 °C
   • D57 °C
   Toon antwoord

   Antwoord: A. 62 °C

   The temperature rises 6 °C per minute. From 50 °C at 5 min, add 2 × 6 = 12 °C to get 62 °C.

7. Vraag 7 van 16

   Which statement best describes the trend in this data?

   Plant food (g per week)	Average height after 3 weeks (cm)
   0	12
   5	18
   10	22
   15	23
   20	23

   • AHeight keeps rising by exactly the same amount for every extra 5 g
   • BHeight rises with plant food up to about 15 g, then levels off
   • CHeight goes down steadily as the amount of plant food goes up
   • DPlant food has no effect on height, because all values are similar
   Toon antwoord

   Antwoord: B. Height rises with plant food up to about 15 g, then levels off

   Height rises from 12 to 23 cm, but there is no change between 15 g and 20 g, so the effect levels off.

8. Vraag 8 van 16

   Between which two amounts of plant food did average height increase the most?

   Plant food (g per week)	Average height after 3 weeks (cm)
   0	12
   5	18
   10	22
   15	23
   20	23

   • A10 g and 15 g
   • B5 g and 10 g
   • C0 g and 5 g
   • D15 g and 20 g
   Toon antwoord

   Antwoord: C. 0 g and 5 g

   The increases are 6, 4, 1 and 0 cm. The biggest jump, 6 cm, is from 0 g to 5 g.

9. Vraag 9 van 16

   What relationship does this data show between ramp height and time?

   Ramp height (cm)	Time to reach bottom (s)
   10	2.4
   20	1.7
   30	1.4
   40	1.2

   • ARamp height has no effect on time
   • BAs ramp height increases, the time increases
   • CTime doubles every time height doubles
   • DAs ramp height increases, the time decreases
   Toon antwoord

   Antwoord: D. As ramp height increases, the time decreases

   Higher ramps give shorter times. When one variable goes up as the other goes down, the relationship is inverse (negative).

10. Vraag 10 van 16

    A toy cart moves at a steady speed. What is its speed?

    Time (s)	Distance travelled (m)
    0	0
    2	24
    4	48
    6	72

    • A6 m/s
    • B24 m/s
    • C12 m/s
    • D72 m/s
    Toon antwoord

    Antwoord: C. 12 m/s

    Speed = distance ÷ time = 72 m ÷ 6 s = 12 m/s. Every 2 s it goes 24 m, which is the same rate.

11. Vraag 11 van 16

    How much more rain fell in June than in April?

    Month	Rainfall (mm)
    April	25
    May	52
    June	94
    July	66

    • A119 mm
    • B28 mm
    • C69 mm
    • D42 mm
    Toon antwoord

    Antwoord: C. 69 mm

    June had 94 mm and April had 25 mm: 94 − 25 = 69 mm.

12. Vraag 12 van 16

    What was the total rainfall for the four months?

    Month	Rainfall (mm)
    April	25
    May	52
    June	94
    July	66

    • A212 mm
    • B186 mm
    • C237 mm
    • D94 mm
    Toon antwoord

    Antwoord: C. 237 mm

    25 + 52 + 94 + 66 = 237 mm.

13. Vraag 13 van 16

    A student counts how many times a pendulum swings in 30 seconds, four times. What is the mean (average) number of swings?

    Trial	1	2	3	4
    Swings in 30 s	14	16	15	15

    • A60
    • B14
    • C16
    • D15
    Toon antwoord

    Antwoord: D. 15

    Mean = (14 + 16 + 15 + 15) ÷ 4 = 60 ÷ 4 = 15.

14. Vraag 14 van 16

    In a spreadsheet of results, a scientist wants to show whether people who walk more steps each day also have lower resting heart rates. Which graph shows the relationship between these two measured values best?

    • AA scatter plot of steps against heart rate
    • BA circle graph of steps
    • CA single bar for each person's name
    • DA line graph of the dates the data was collected
    Toon antwoord

    Antwoord: A. A scatter plot of steps against heart rate

    A scatter plot puts one value on each axis, so you can see if the points form a trend.

15. Vraag 15 van 16

    Data shows that the number of hours of daylight in a northern town increases from January to June. What can you best estimate from this pattern?

    • AEvery month has the same daylight
    • BDaylight in the town will never decrease
    • CJune has fewer daylight hours than January
    • DMarch has more daylight hours than January
    Toon antwoord

    Antwoord: D. March has more daylight hours than January

    The trend is increasing from January to June, so a month between them, like March, should be higher than January. Predicting beyond the data, like "never decrease", is not supported.

16. Vraag 16 van 16

    Why is estimating a value far outside the range of measured data (extrapolating) risky?

    • AMeasured data cannot be put on a graph at all
    • BIt is against the rules of science and is never allowed
    • CThe trend may change outside the tested range
    • DIt always gives a negative number that cannot be used
    Toon antwoord

    Antwoord: C. The trend may change outside the tested range

    A pattern seen in your data might not continue. For example, plant food helps plants grow only up to a point.

Toetsenbord: 1–4 om te antwoorden, Enter voor de volgende vraag.

Het echte examen: 55% on each CAEC test