Lesson 19 Accuracy and errors
Worksheet 1 Accuracy and errors
Accuracy on the number line
- In a skiing competition, the time a skier takes to ski between two posts is recorded to the nearest tenth of a second. The competitors ski down two slopes.
Jane’s times for the two ski slopes were 2.7 seconds and 1.9 seconds. Show a way of finding Jane’s total time using the number line. Is there another way?

2. Mary’s total skiing times for the two slopes appear to be the same time as Jane’s by my clock. Still the organisers were able to decide on one winner. How could they do that?
Write some ideas or examples. You may use the enlarged portion of the number line below to show your work.

3. How many different numbers can you think of between any two markers on the
number line?
Explain and give examples.