Skip to main content
### Number and algebra

### Geometry and measure

### Probability and statistics

### Working mathematically

### For younger learners

### Advanced mathematics

# Warmsnug Double Glazing

## You may also like

### Compare Areas

### Take a Square

### Semi-detached

Links to the University of Cambridge website
Links to the NRICH website Home page

Nurturing young mathematicians: teacher webinars

30 April (Primary), 1 May (Secondary)

30 April (Primary), 1 May (Secondary)

Or search by topic

Age 14 to 16

Challenge Level

- Problem
- Getting Started
- Student Solutions
- Teachers' Resources

Start by looking at the windows with only one pane.

Are there any windows that use the same amount of glass?

How do their frame lengths differ?

Are there any windows that use the same amount of frame?

How do their glass areas differ?

Click to reveal a handy table with the areas and frame lengths of all the windows:

Length of frame |
Area | Cost | |

A | 28 | 32 | £880 |

B | 16 | 15 | £470 |

C | 12 | 8 | £320 |

D | 20 | 16 | £560 |

E | 18 | 12 | £550 |

F | 12 | 9 | £330 |

G | 26 | 24 | £760 |

H | 8 | 3 | £190 |

I | 14 | 12 | £400 |

J | 8 | 4 | £200 |

K | 17 | 12 | £460 |

L | 23 | 20 | £660 |

M | 24 | 36 | £840 |

N | 20 | 24 | £640 |

O | 16 | 12 | £440 |

Which has the greatest area, a circle or a square, inscribed in an isosceles right angle triangle?

Cut off three right angled isosceles triangles to produce a pentagon. With two lines, cut the pentagon into three parts which can be rearranged into another square.

A square of area 40 square cms is inscribed in a semicircle. Find the area of the square that could be inscribed in a circle of the same radius.