# Teacher Notes

### Why use this resource?

This resource is designed to develop a sense of what logarithms are, how they can be used and the sort of values they take. Log tables are used to perform a selection of multiplications and other calculations.

In addition, the resource offers some exercising of other skills such as

• Working with numbers in standard form.
• Using the laws of logs.
• Rounding to significant figures.
• Reading mathematical tables. While log tables are no longer in use, this is a transferable skill that is still useful in many other contexts.

### Preparation

Copies of the log tables will be need to be printed for the students.

### Possible approach

Show the exam question and ask how students would tackle it without a calculator. How could logarithms help?

Show the simpler sum and ask students to complete step 1 (standard form) possibly as a “show-me” exercise.

Show the videos one by one discussing and bringing out the point after each one (each calculation step).

### Key questions

• How do logarithms help make these questions easier?
• What are the limitations? (This can nicely lead into the section on difference tables.)