Can you use the digits on the left of this clock along with any mathematical operations to equal the digits on the right (also with any mathematical operations)?

Examples

Which times is this possible and which times impossible?

Alternate activity

Use the digits of the current time to make as many different calculations as possible all with different answers.

All four digits must be used and each must appear once only in each of your calculations.

Next choose a different time that you think will produce more calculations than the present time.

A Mathematics Lesson Starter Of The Day

• Transum,
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• The key to making this activity a successful starter is not just considering the current time but focussing on the question 'Which times is this possible and which times impossible?'. The question 'How many times can you find that are possible?' might lead to a list of similar mathematical operations (which is fine for some pupils) while dividing the class into small groups and assigning each group an hour of the day may encourage some more creativity. Let us know if your class make any interesting discoveries.

How did you use this starter? Can you suggest how teachers could present or develop this resource? Do you have any comments? It is always useful to receive feedback and helps make this free resource even more useful for Maths teachers anywhere in the world.

Previous Day | This starter is for 14 June | Next Day

 09 01 0x9=0 0x1=0 09 02 0x9=0 0x2=0 09 03 0x9=0 0x3=0 09 04 0x9=0 0x4=0 09 05 0x9=0 0x5=0 09 06 0x9=0 0x6=0 09 07 0x9=0 0x7=0 09 08 0x9=0 0x8=0 09 09 90 90 09 10 0x9=0 1x0=0 09 11 90=1 11=1 09 12 90=1 12=1 09 13 90=1 13=1 09 14 90=1 14=1 09 15 90=1 15=1 09 16 90=1 16=1 09 17 90=1 17=1 09 18 90=1 18=1 09 19 90=1 19=1 09 20 0x9=0 0x2=0 09 21 √9+0=3 2+1=3 09 22 90=1 2÷2=1 09 23 0+9=9 32=9 09 24 √9+0=3, 3!=6 2+4=6 09 25 √9+0=3 5-2=3 09 26 √9+0=3 6÷2=3 09 27 0+9=9 2+7=9 09 28 90=1 82=64, 6+4=10, 1+0=1 09 29 0+9=9 92=81, 8+1=9 09 30 0x9=0 0x3=0

For more ideas see Alan Sturgess' Maths Puzzle Investigation video.

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 Teacher, do your students have access to computers?Do they have iPads or Laptops in Lessons? Whether your students each have a TabletPC, a Surface or a Mac, this activity lends itself to eLearning (Engaged Learning).

Here a concise URL for a version of this page without the comments.

Transum.org/go/?Start=June14

Here is the URL which will take them to a related student activity.

Transum.org/go/?to=fifteen