Q.

If A is a 3×3 matrix such that |A|=8, then |3A| equals:

1 8  
2 24  
3 72  
4 216  

Ans.

(4)

Ans.     216

Explanation:

Given:                |A|=8

We know that,  |kA|=kn|A|, where k is a constant 

∴                    |3A|=33|A|=27×8=216