Jose thinks of a number.
He multiplies this number by 9 then subtracts 9.
His answer is 45. What was Jose's original number?
Jose's friend thinks of a number.
He then does the following operations:
Multiply by 2, subtract 3, multiply by 3 then add 21 (in that order). He finds that the number he ends up with is 9 times his original number.
What was Jose's friend's original number?
Change NumbersEasier Questions
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.
Too difficult? There are some simpler questions like this on the THOAN Starter page.
Sign in to your Transum subscription account to see the answers
Note to teacher: Doing this activity once with a class helps students develop strategies. It is only when they do this activity a second time that they will have the opportunity to practise those strategies. That is when the learning is consolidated. Click the button above to regenerate another version of this starter from random numbers.
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 link. As an Amazon Associate I earn a small amount from qualifying purchases which helps pay for the upkeep of this website.Educational Technology on Amazon
Teacher, do your students have access to computers such as tablets, iPads or Laptops? This page was really designed for projection on a whiteboard but if you really want the students to have access to it here is a concise URL for a version of this page without the comments:
However it would be better to assign one of the student interactive activities below.
Here is the URL which will take them to the Think Of A Number exercise.
Here is the URL which will you to our eQuation Generator which provides unlimited practice solving linear equations.