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## 'Big and Small Numbers in Physics' printed from http://nrich.maths.org/

### Why do this problem?

The ability to work with big and small numbers is a very important scientific skill. These

questions provide a variety of contexts where handling such numbers is necessary, while offering practice at identifying key information and making decisions about estimates and assumptions.

### Possible approach

These questions could be used individually as starters or fillers within lessons. Alternatively, a class could work on different questions in small groups and then present their answers with reasoning to the rest of the class to stimulate discussion. Some questions can be tackled with little specialist knowledge; others may require research and additional information, as well as some
assumptions, in order to come up with an answer.

It is important to stress that there is no "correct" answer for some of these questions - the value of this task comes from having a go at estimating and calculating with big and small numbers, and discussing assumptions that need to be made and extra data that need to be sought in order to find a solution.

### Key questions

What assumptions have you made?

What other information do you need?

Are there any questions which give an exact answer? Can you say anything about the accuracy of those answers which aren't exact?

### Possible extension

This problem could be done in conjunction with

Big and Small Numbers in Biology. Similar questions could be created and shared within the class.

### Possible support

Start with those questions which have familiar content, and encourage whole class discussion of the ideas in them, before tackling any of the questions which require extra information. It is well worth suggesting that students read the article

Student Guide to Getting Started with Rich Tasks before tackling a very open
problem like this one.