'Plausible Estimation' Estimates
for a Million Tasks - Set #1
Malcolm Swan
Mathematics Education
University of Nottingham
Malcolm.Swan@nottingham.ac.uk
Jim Ridgway
School of Education
University of Durham
Jim.Ridgway@durham.ac.uk
The aim of this assessment is to provide the opportunity for you to:
· develop a chain of reasoning that will enable you to estimate quantities to an
appropriate degree of accuracy
· choose suitable units for your estimate
· communicate the assumptions upon which your estimate is based.
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1. Breathing
How many days would it take you to breathe a million times?
Assumptions
Reasoning
2. Paper Clips
Suppose a chain is made from a million paper clips. How far will it stretch?
Choose suitable units for your answer.
Assumptions
Reasoning
3. The brick wall
Suppose you use a million household bricks to build a wall four feet high. How long would the
wall be?
Assumptions
Reasoning
4. The dripping faucet
A faucet drips a million times. How many buckets will it fill?
Assumptions
Reasoning
5. Writing a million
How long would it take you to write out all the numbers, from one to a million?
Remember that some numbers have more digits than others!
Assumptions
Reasoning