Brainteasers

3rd September 2004 at 01:00
Puzzles to test mathematical skills, set by Anita Straker. Solutions below More brainteasers on www.tes.co.ukteacherbrainteasers

Ages 7-11

Find the pattern

The letters A to J stand for 10 numbers in a number pattern.

The sum of any three adjacent numbers in the pattern is 10.

B is 2, and J is 5.

What are the 10 numbers?

Ages 11-14

Ring of good fortune

Six equal small circles are drawn in contact with a large circle as shown.

The radius of the large circle is 12cm.

What is the radius of the small circles?

SOLUTIONS Ring of good fortune The radius of the smaller circle is 4cm.

Triangle OAB is equilateral, so OB is twice the radius of the small circle.

BR equals the radius of the small circle. So the radius of the large circle is three times the radius of the small circle.

SOLUTIONS Find the pattern JJJ If B is 2, then C + D = 8, E = 2, F + G = 8, * = 2 and I+J=8. Since J = 5, I = 3. Since I = 3 and H = 2, G = 5. Since F + G = 8 and G = 5, F = 3. Since F = 3 and E =2, D = 5. Similarly, it follows that C = 3 and A = 5.

Subscribe to get access to the content on this page.

If you are already a Tes/ Tes Scotland subscriber please log in with your username or email address to get full access to our back issues, CPD library and membership plus page.

Not a subscriber? Find out more about our subscription offers.
Subscribe now
Existing subscriber?
Enter subscription number

Comments

The guide by your side – ensuring you are always up to date with the latest in education.

Get Tes magazine online and delivered to your door. Stay up to date with the latest research, teacher innovation and insight, plus classroom tips and techniques with a Tes magazine subscription.
With a Tes magazine subscription you get exclusive access to our CPD library. Including our New Teachers’ special for NQTS, Ed Tech, How to Get a Job, Trip Planner, Ed Biz Special and all Tes back issues.

Subscribe now