What is the longest sequence you can make from the numbers below?

 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Each number in the sequence must be a factor or multiple of the previous number.

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Topics: Starter | Arithmetic | Factors | Mental Methods | Number

• Transum,
•
• This is a fascinating activity on a number of levels. It is accessible to pupils who have learned about factors and multiples and need practice but it also proves to be an interesting activity for older pupils who may analyse the situation from a more general perspective. Finding the best solution and being sure that it can't be bettered is a challenge for the most able. What strategies did your class come up with?
• Mrs M,
•
• Good to revise factors and multiples.
• WKGS, Wirral
•
• We got 18!
• Paula, Portsmoiuth
•
• I got 20!
• Katy, Sydney
•
• Got 21! Definitely going to this to extend my students.
• Room 5, Cool School
•
• WE got 21 too!! Took us afew goes but we think 21 is brilliant.
• Mr S, Haslemere
•
• We got 20, please post solution for 21.
• Kai and Finn, 5M
•
• Finn and I got 20. WOW!
• Luca, Canberra, Australia
•
• I got 20 but still working on it.
• Oliver, Tenterden Joinior
•
• Amazing I got the best score in my class 15.
• Miss Collins,
•
• This a really great starter for my class. It makes you think a lot.

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This starter has scored a mean of 3.7 out of 5 based on 3 votes.

Previous Day | This starter is for 7 May | Next Day

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## A Compendium Of Mathematical Methods

How many different methods do you know to solve simultaneous equations? To multiply decimals? To find the nth term of a sequence?

A Compendium of Mathematical Methods brings together over one hundred different approaches from classrooms all over the world, giving curious mathematicians the opportunity to explore fascinating methods that they've never before encountered.

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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).

Transum.org/go/?Start=May7

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

Transum.org/go/?to=factortrees

## Curriculum Reference

See the National Curriculum page for links to related online activities and resources.

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