Half Hearted


Find the number which when added to the top (numerator) and bottom (denominator) of each fraction make it equivalent to one half. more...


Topics: Starter | Algebra | Fractions

  • Transum,
  • It must seem strange to so many people that you can multiply the top and bottom of a fraction by the same number and the fraction's value remains the same but when you add the same number to top and bottom the fraction's value changes.

    Then we think of equations and the rules are different. You can multiply or add to both sides and the equation remains balanced.

    What is your best explanation for that?
  • David Payne, Secondary Maths Teacher
  • I use your starters a lot. Thank you for such a thought provoking, varied and rich set of activities.

    We did the May 22nd “Half hearted” starter today and one of the pupils pointed out that d-n = the new numerator. Gasps all around. Why? How can it be? And that was just me. I have now worked it out using your extension activity but it seemed like a really surprising result at first.

    I just hope it doesn’t encourage the students to add a number to the numerator and denominator in any other contexts. I did tell them not to try this at home.

    Anyway, thanks, and keep up the good work.

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 2.9 out of 5 based on 499 votes.

Previous Day | This starter is for 22 May | Next Day



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.



Extension activities

Find the number which when added to the numerator and denominator of each of the fractions above make them equivalent to one third.

What should be added to the numerator and denominator of the fraction whose numerator is n and denominator is d to make it equivalent to one half?

What should be added to the numerator and denominator of the fraction whose numerator is n and denominator is d to make it equivalent to one third?

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.


Have you read Craig's book yet?

Craig Barton must surely be the voice of Mathematics teachers in the UK. His wonderful podcasts interviewing the industry experts have culminated in this wonderful book. As Craig says: "I genuinely believe I have never taught mathematics better, and my students have never learned more. I just wish I had known all of this twelve years ago..." more...

"How I wish I'd taught Maths" is an extraordinary and important book. Part guide to research, part memoir, part survival handbook, it’s a wonderfully accessible guide to the latest research on teaching mathematics, presented in a disarmingly honest and readable way. I know of no other book that presents as much usable research evidence on the dos and don’ts of mathematics teaching in such a clear and practical way. No matter how long you have been doing it, if you teach mathematics—from primary school to university—this book is for you." Dylan Wiliam, Emeritus Professor of Educational Assessment, UCL.

The Craig Barton Book

Casio Classwiz Calculator

There is currently a lot of talk about this new calculator being the best in its price range for use in the Maths classroom. The new ClassWiz features a high-resolution display making it easier to view numerical formulas and symbols but it isn't a graphical calculator as such (it has the capacity to draw graphs on your smart phone or tablet, via a scannable QR code and an app).

As well as basic spreadsheet mode and an equation solving feature you also get the ability to solve quadratic, cubic or quartic polynomial inequalities and the answer is given just as it should be written down, using the correct inequality symbols!

This calculator has a high-performance processor and twice the memory of previous models ensuring speedy operation and superior computational power.more...

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 related student activity.


Student Activity

A glass ½ full = A glass ½ empty

Multiply both sides by two

A full glass = An empty glass



Extension Answers


©1997-2020 WWW.TRANSUM.ORG


Adding two to the numerator and denominator of one quarter produces a fraction equivalent to one half.


Half Hearted Examplde