Back to Calculation Tips & Tricks

Squaring Numbers

Multiplying Numbers

Dividing Numbers

Adding Numbers

Subtracting Numbers

Finding Percents

Calculation Practice Exercises

Full List

one less nine than the number 9 9 9 one 8 8 the same number of zeros as 9's 0 0 0 a final 1 1

See the pattern?

one less nine than the number 9 9 9 9 9 one 8 8 the same number of zeros as 9's 0 0 0 0 0 a final 1 1

This is not a very demanding mental math exercise, but it is an interesting pattern.

[Privacy Policy] [Terms of Use]

Home || The Math Library || Quick Reference || Search || Help