# Just Jottings (16-18)

This collection of tasks is part of the activities for 16-18 year olds section of the Maths At Home feature. All you need to get started is a pencil and paper! The stars represent the challenge level, with three stars indicating the most challenging activities.

You may also wish to explore Just Jottings for 14-16 year olds.

### Why 24?

##### Age 14 to 16Challenge Level

Take any prime number greater than 3 , square it and subtract one. Working on the building blocks will help you to explain what is special about your results.

##### Age 14 to 16Challenge Level

If a sum invested gains 10% each year how long before it has doubled its value?

### Root Hunter

##### Age 16 to 18Challenge Level

In this short problem, try to find the location of the roots of some unusual functions by finding where they change sign.

### Partly Circles

##### Age 14 to 16Challenge Level

What is the same and what is different about these circle questions? What connections can you make?

### Curved Square

##### Age 16 to 18Challenge Level

Can you find the area of the central part of this shape? Can you do it in more than one way?

### Quick Sum

##### Age 16 to 18 ShortChallenge Level

Is this surd sum exactly 3?