Coins On The Table

Coin Coin Coin Coin Coin Coin Coin Coin Coin Coin Coin

Some coins were arranged in a row.
Half of them were tails up.
Two of the coins are turned over and now one third of them are tails up.
How many coins were in the row?

Coin Coin Coin Coin Coin Coin Coin Coin Coin Coin Coin

Teacher: Here is a visual aid to use if required. Coins can be dragged and, to turn them over, doubleclick.

Have a guess!


Topics: Starter | Fractions | Problem Solving | Puzzles

  • Mrs A Milton, Ysgol Ardudwy
  • I have used your starters for 3 years now and would not have a lesson without one! Fantastic way to engage the pupils at the start of a lesson.
  • The Best Maths Group Ever 7cd/M2, King Alfred's College, Oxfordshire
  • Some of us caught on quickly. But majority found it tricky. Drawing coins helped to explain the answer.
  • Rachel, Claverham
  • You should have been more specific with the wording and said that the tails were turned over.
  • Francis, Halifax
  • The wording of the question is fine. If 1/2 of the coins start as tails up, and, when 2 are turned this becomes 1/3, it should be obvious that it was tails that were turned because 1/3 is less than 1/2.
  • Gabriel, Edgware
  • The wording is a problem...
    If you started with 6 coins and turned one head and one tail over, you would get to 1/2 and 1/3.
  • Primary 7, Bargeddie Primary School
  • The majority of our class found this very confusing at first. However, Lewis in our class worked out the answer very quickly: he worked out that if he thought of a number on the 2 times table, and tried to take 2 away to see if it was on the three times table then he would have his answer...
    The rest of the class were most impressed!
  • Nick, Weston
  • This was epic.
  • Sarah, Tenbury
  • I think your algebraic answer is harder than it needs to be. if you say
    x/2 - 2 = x/3 (+2 and -x/3 on both sides then

    x/2 - x/3 = 2 (x6 both sides)
    3x - 2x = 12 so x=12.
  • Mr Miller, Brough Primary
  • One child in our class found this particularly confusing but she eventually understood after much discussion and debate with the teacher!
    Everybody else found it interesting, if not challenging.
  • Holly Walton, Calmore Junior School
  • Really good website.
  • Matthew Zhao, 5S, Craigslea State Primary School
  • Challenging for average grade 5s, although very easy for my intelligent brain and my quick way of using Trial and Error. =).

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 3.0 out of 5 based on 923 votes.

Previous Day | This starter is for 16 March | 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 chosen and recommended by Transum Mathematics to get you started.


Texas Instruments Nspire Calculator

This handheld device and companion software are designed to generate opportunities for classroom exploration and to promote greater understanding of core concepts in the mathematics and science classroom. TI-Nspire technology has been developed through sound classroom research which shows that "linked multiple representation are crucial in development of conceptual understanding and it is feasible only through use of a technology such as TI-Nspire, which provides simultaneous, dynamically linked representations of graphs, equations, data, and verbal explanations, such that a change in one representation is immediately reflected in the others.

For the young people in your life it is a great investment. Bought as a gift for a special occasion but useful for many years to come as the young person turns into an A-level candidate then works their way through university. more...

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.

Click the images above to see all the details of these items and to buy them online.

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


Do you think a fraction wall might help with this puzzle?


©1997-2020 WWW.TRANSUM.ORG