English Deutsch Français Italiano Español Português 繁體中文 Bahasa Indonesia Tiếng Việt ภาษาไทย
All categories

I know the common method is to multiply it three times. But, that would require paper and pen / pencil. I want to learn the mental calculation method. Please let me know how.
Thanks

2006-12-23 05:41:36 · 2 answers · asked by anjana s 1 in Science & Mathematics Mathematics

2 answers

The cubes of numbers from 1 to 11 are easy to do in your head, right?

1, 8, 27, 64, 125, 216, 343, 512, 729, 1000, 1331

Some of the others are easy. Cubes of 20, 30, 40, 50, 60 - just add three zeros to cubes of 2, 3, 4, 5, 6.

16^3 is the same as 2^12, so 4096. (that's 4*1024 if you only know the powers of two up to 2^10)

32^3 is the same as 2^15, so 32,768. (assume you know the powers of two fairly high)

You just have to pick up the tricks.

2006-12-23 06:29:23 · answer #1 · answered by Steve A 7 · 0 0

multiply and divide equally

2006-12-23 13:51:02 · answer #2 · answered by Anonymous · 0 2

fedest.com, questions and answers