How many minutes between?

How many minutes between?

Auto-markingPencil and paperOnline interactive
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Working with Students
Further Resources
This task is about working out the difference between two times in minutes.
 
stopwatch.png
 How many minutes are there between each of the following times on the same day?

Question 2Change answer

a)  3:30 p.m. and 5:30 p.m.  minutes

Question 2Change answer

b)  4:20 p.m. and 9:05 p.m.  minutes

Question 2Change answer

c)  8:55 a.m. and 2:20 p.m.  minutes

Question 2Change answer

d)  3:40 a.m. and 11:30 p.m.  minutes
Task administration: 
This task can be completed with pencil and paper or online (with auto marking displayed to students).
Level:
4
Curriculum info: 
Maths, Geometry and Measurement, Measurement
Keywords: 
time, subtraction, addition, multiplication, minutes, conversion of units
Description of task: 
Students answer questions about the difference between a range of given times in minutes.
Curriculum Links: 
This resource can help to identify students' understanding of working with and converting measurement units of time for the Measurement objectives, and multiplicative strategies for the Number and Algebra objectives.
Learning Progression Frameworks
This resource can provide evidence of learning associated with
Multiplicative thinking, sets 6-7
within the Mathematics Learning Progressions Frameworks.
Read more about the Learning Progressions Frameworks.
Answers/responses: 
   Y7 (07/1997) Y8 (07/1997)
a) 120 easy very easy
b) 285 difficult moderate
c) 325 difficult moderate
d) 1190 very difficult difficult
Diagnostic and formative information: 
  Common error Likely calculation Likely misconception
a)
b)
c)
d)		 200
485 or 4.85
635 or 6.35
790 or 7.90		 530 – 330
905 – 420
855 – 220
1130 – 340		 Assumes 100 minutes per hour.
b) 345 5 × 60 + 45 Subtraction error – (renaming error)
b) 240.45 4 × 60 + .1 × (45) Incorrect numeration concepts (wrong place value).
d) 470 7 × 60 + 50 Assumes 11:30 a.m. rather than p.m.
b)-d) Many different answers were given that indicate numeration or subtraction errors. Students sometimes show different misconceptions in different parts.