Question

What are the digits in the unit’s place of the cubes of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10? Is it possible to say that a number is not a perfect cube by looking at the digit in unit’s place of the given number, just like you did for squares?

Answer 1

1³ = 1

2³ = 8

3³ = 27

4³ = 64

5³ = 125

6³ = 216

7³ = 343

8³ = 512

9³ = 729

10³ = 1000

The digits at units place are 1, 8, 7, 4, 5, 6, 3, 2 and 9.

Each digit occurs at the end of some cube.

Hence, one cannot conclude that a number is not a perfect cube by looking at its unit digit.