S K Gupta and Anubhuti Gangal Solutions for Chapter: Cubes and Cube Roots, Exercise 3: Mental maths

What is the smallest number by which $81$ should be divided to make it a perfect cube?  

Find the cube root of $\frac{27}{64}$. 

Find the cube root of $0.008$.  

Find the cube root of $-27000$.   

Find the cube root of $-27000$ 

Find the perfect cube in the following:

$27, 64, 125, 98, 100, -8000, -9000$

Simplify:

${10}^2-4^3$

Evaluate:

$\sqrt[3]{0.001}\times 10$