This is a game for two players. Let's call them A and B.

A begins by typing any number into a calculator.

B then multiplies this number by another number, trying to get the answer as close as possible to 100.

A then multiplies this number by another number, trying to get even closer to 100.

The winner is the first player to make the total equal a hundred point something.

Play the game many times. Can you find a good strategy for winning?



A Transum Maths Starter Of The Day



Topics: Starter | Arithmetic | Calculator | Decimals | Estimating | Games

  • Nikki, Devon
  • Excellent. A great reminder for kids who have just been investigating what happens when you multiply or divide a number by a value between 0 and 1. Thanks
  • Transum,
  • This is starter for two students working together. There is a lot to be gained from pupils collaborating on problem solving as they not only learn from their partner but also benefit from practising putting their thoughts into words so their partner can follow their line of reasoning. Technically this starter puts one pupil in competition against the other but all of the other Starters of the Day can be presented in a 'working together' format either in pairs or small groups.
  • Matthew Zhao, 4AD, Craigslea State School
  • A great mental teaser to let me think about a great way of a never-ending game. Just simply have Player A enter 0 into the calculator, then nobody can ever win because 0x(any number) will always be 0!

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 3.1 out of 5 based on 458 votes.

Previous Day | This starter is for 5 October | Next Day


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 I have chosen and recommend to get you started. As an Amazon Associate I earn a small amount from qualifying purchases which helps pay for the upkeep of this website.


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 similar number puzzle.

Student Activity


©1997-2020 WWW.TRANSUM.ORG