Te Kete Ipurangi Navigation:

Te Kete Ipurangi
Communities
Schools

Te Kete Ipurangi user options:

Level Two > Geometry and Measurement

How Many Strips?

Keywords:
Achievement Objectives:

Achievement Objective: Create and use appropriate units and devices to measure length, area, volume and capacity, weight (mass), turn (angle), temperature, and time.

Specific Learning Outcomes: 

Measure using cm and metres

Use additive strategies

Devise and use problem solving strategies to explore situations mathematically (use equipment)

Description of mathematics: 

This is first a practical measuring task coupled with some arithmetic. The most efficient way to do this problem is by measuring the length of an A4 sheet and dividing 1m by this length. However, sticking strips together and measuring until the strips have reached 1m in length is another way to solve the problem. The number of strips can then be counted.

It might be a good idea to try the first method and then check it by the practical method. It is possible that there might be a difference between the two methods if the strips have not been laid end to end carefully enough.

There is a little twist in this problem in that the length of a strip doesn’t divide 1m exactly. So the students will have to realise that to make up the full 1m they have to tear off an ‘extra’ strip.

Required Resource Materials: 
A4 sheets of paper
1 metre and 30 cm rulers
Copymaster of the problem (English)
Copymaster of the problem (Māori)
Activity: 

Problem

Take one A4 sheet of paper. Tear or cut it into strips length-wise. How many strips will you need to make up a length of 1m by laying the strips end to end?

Teaching sequence

  1. Interest the students in the problem by asking them to stand 1 metre from a given line. Check estimates.
  2. Reinforce their estimates of 1 metre by asking questions that encourage the students to develop a "sense" of a metre.
    What lengths are 1 metre long?
  3. Pose the problem.
  4. As the students work on the problem check their use of rulers to measure the length of the A4 paper and the metre strip.
    How many centimetres are there in a metre? How do you know? (100 on the ruler)
  5. Share solutions

Extension to the problem

What is the longest strip that you could make using a single sheet of A4 paper with no joins?

Solution

An A4 sheet is approximately 29.7cm long. 100 divided by 29.7 is 3 and some left over. To make at least 1m requires four A4 lengths.

Extension:

There is a theoretical limit to the length that you can make.  If you use very thin strips you can get an extremely long strip.  Send us in the length of your classes best effort.  We'll let you know the longest we have heard of.


 

AttachmentSize
HowManyStrips.pdf53.57 KB
HowManyStripsMaori.pdf56.51 KB

Similar Resources

Three Chairs

This is a level 3 measurement strand activity from the Figure It Out series.

Mighty Metres

This is a level 2 measurement strand activity from the Figure It Out series.

Measurement Investigations 2

The students will complete a number of practical measuring investigations, with an emphasis on accuracy of measuring and communication of their findings.

Snails

Measure using cm.

Solve problems using minutes as the unit.

Devise and use problem solving strategies to explore situations mathematically

Trains

Compare two lengths (either directly or by calculation)

Devise and use problem solving strategies to explore situations mathematically