ICAS Interpreting Scientific Data 3 — Questions and Answers
Question 1: A scatter plot shows data points mostly following an upward trend from left to right. What type of correlation does this represent?
- Negative correlation
- No correlation
- Positive correlation (Correct answer)
- Inverse correlation
Correct answer: Positive correlation
Points trending upward from left to right show a positive correlation between the two variables.
Question 2: Scientists measure rainfall (mm) and river depth (m) over 6 months. As rainfall increases, river depth also increases. This relationship is best described as:
- Coincidental
- Inversely proportional
- Directly proportional (Correct answer)
- Unrelated
Correct answer: Directly proportional
When one variable increases as the other increases proportionally, the relationship is directly proportional.
Question 3: A data table shows that an ice cube's mass decreases over time as it melts. After 10 minutes it has lost 40% of its mass. If it started at 50 grams, what is its current mass?
- 10 g
- 20 g
- 30 g (Correct answer)
- 40 g
Correct answer: 30 g
40% of 50 g = 20 g lost, so 50 − 20 = 30 g remaining.
Question 4: A graph shows two lines: one for indoor temperature and one for outdoor temperature over 24 hours. The indoor line changes much less than the outdoor line. What does this tell us?
- Outdoor temperature is always warmer
- Indoor temperature fluctuates more
- Indoor conditions are more stable than outdoors (Correct answer)
- The outdoor sensor is broken
Correct answer: Indoor conditions are more stable than outdoors
A line with smaller variation indicates more stable conditions, showing indoors is better regulated.
Question 5: A scientist conducts an experiment with a control group and an experimental group. What is the purpose of the control group?
- To make the experiment faster
- To provide a baseline for comparison (Correct answer)
- To increase the sample size
- To replace the experimental group
Correct answer: To provide a baseline for comparison
The control group provides a baseline with no treatment applied, allowing comparison with the experimental results.
Question 6: A frequency table shows how many students scored in each grade range on a science test. The 70–79 range has the highest frequency. What does this mean?
- Most students failed the test
- Most students scored between 70 and 79 (Correct answer)
- The test was too easy
- No student scored above 79
Correct answer: Most students scored between 70 and 79
Highest frequency in the 70–79 range means more students scored there than in any other range.
Question 7: An experiment measures how quickly sugar dissolves in water at different temperatures. Results show it dissolves fastest at 80°C. Which conclusion is best supported?
- Sugar does not dissolve below 80°C
- Higher temperature increases the rate of dissolving (Correct answer)
- Sugar dissolves equally fast at all temperatures
- Cold water is better for dissolving sugar
Correct answer: Higher temperature increases the rate of dissolving
Since dissolving rate increases with temperature and peaks at 80°C, higher temperature speeds up dissolving.
ICAS Interpreting Scientific Data 3
A scatter plot shows data points mostly following an upward trend from left to right.
What type of correlation does this represent?