A Mathematics Lesson Starter Of The Day

Drag the numbers into the yellow circles so that the totals along each side of the triangle are the same.







Once you have completed the above challenge, can you then rearrange the numbers so the total of each side is now different to your first solution. How many ways can this be done?


Now try this version:

Drag the numbers into the yellow circles so that the totals along each side of the triangle are the same.







Here are some more challenging, self checking, versions of this activity using:

the digits 2 to 7 the digits 3 to 8 multiples of 4 negative numbers random numbers

What if there were nine digits to place on the sides of the triangle? See Triside Totals:

Puzzle 1 Puzzle 2 Puzzle 3 Puzzle 4 Puzzle 5


Topics: Starter | Arithmetic | Investigations | Puzzles

  • Clue Giver,
  • Easy! Clue: 1st triangle= 9, 2nd= 18.
  • Jules, Devon
  • Brilliant.Got 12 on each side on the first one, 21 on each side for the second. If the children get stuck tell them to use the highest three numbers on the corners, bit of jigging and it always works.
  • Kashyap, Mt Roskill Intermediate, Auckland
  • Simple, either place the biggest three in the corners or the middle of the triangle, after that its easy.
  • Mathemaniac, South Wales
  • This can be used to demonstrate reflection and rotation (to get different triangles) and inversion (take each number from your first solution from 7).
  • Transum,
  • Don't miss the link below ('') which leads to a self-checking version of this activity for which pupils can earn trophies! One for each of the six levels. There is a method or strategy for solving this kind of puzzle and it is only when pupils have solved a number of different versions of the puzzle does the method become apparent.
  • Edward, Bolton
  • Nice activity great fun.
  • Mr Gray, Twitter
  • Friday, June 14, 2019

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.
Click here to enter your comments.

If you don't have the time to provide feedback we'd really appreciate it if you could give this page a score! We are constantly improving and adding to these starters so it would be really helpful to know which ones are most useful. Simply click on a button below:

Excellent, I would like to see more like this
Good, achieved the results I required
Didn't really capture the interest of the students
Not for me! I wouldn't use this type of activity.

This starter has scored a mean of 3.3 out of 5 based on 356 votes.

Previous Day | This starter is for 13 June | Next Day



Click here for a full set of answers.

There is a printable worksheet to go with this activity.


Your access to the majority of the Transum resources continues to be free but you can help support the continued growth of the website by doing your Amazon shopping using the links on this page. Below is an Amazon search box and some items chosen and recommended by Transum Mathematics to get you started.


Rubiks Cube Puzzle

Apple iPad Pro

The analytics show that more and more people are accessing Transum Mathematics via an iPad as it is so portable and responsive. The iPad has so many other uses in addition to solving Transum's puzzles and challenges and it would make an excellent gift for anyone.

The redesigned Retina display is as stunning to look at as it is to touch. It all comes with iOS, the world's most advanced mobile operating system. iPad Pro. Everything you want modern computing to be. more...

Before giving an iPad as a Christmas gift you could add a link to iPad Maths to the home screen.

Math with Bad Drawings

I had been tutoring the wonderful Betsy for five years. When the day came for our last ever session together before the end of her Year 13, I received this beautiful book as a gift of appreciation.

This a very readable book by Ben Orlin. I'm really enjoying the humour in the writing and the drawings are great.

Ben Orlin answers maths' three big questions: Why do I need to learn this? When am I ever going to use it? Why is it so hard? The answers come in various forms-cartoons, drawings, jokes, and the stories and insights of an empathetic teacher who believes that mathematics should belong to everyone.

Online Maths Shop

Laptops In Lessons

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).

Laptops In Lessons

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

Here is the URL which will take them to a student version of this activity.

Student Activity


©1997-2019 WWW.TRANSUM.ORG