Question

24389 is a perfect cube find the unit digit of its cube root
1.3
2.7
3.9
4.1​

Answer 1

(3) 9

We know that

${3}^{3} = 27 \\ {7}^{3} = 343 \\ {9}^{3} = 729 \\{1}^{3} = 1$

Out of these, only (c) 9³ ends in 9. Therefore unit digit of ³√24389 is 9.

$\sqrt[3]{24389} = 29$