At the time of writing the hour and minute hands of my clock are at
right angles. How long will it be before they are at right angles
Derive a formula for finding the area of any kite.
A circle with the radius of 2.2 centimetres is drawn touching the sides of a square. What area of the square is NOT covered by the circle?
The problem presents many different quantities and units. It involves thinking about large and small numbers and 'back of an envelope' estimations and unit conversions. It offers an ideal opportunity for class discussion and convincing arguments.
Challenge students to get "100% in 3 tries" twice in a row!
Print a few copies of some of the 15 question tables (see note at end of the problem). Ask students to identify all the items on one sheet which measure length, say. They could delete all other items and all inappropriate units. In small groups, ask students to estimate the different lengths in any units of their choice, and convert these estimates to other sensible units. Based on this
working, ask them to match up item, number and unit for all the lengths.