Question 24

If the mean of a, b and c is $$M$$; ab + bc + ca = 0; and the mean of $$a^{2}$$, $$b^{2}$$ and $$c^{2}$$ is $$KM^{2}$$ then $$K$$ is equal to

It is given that $$ab+bc+ca=0$$

The mean of $$a^{2}$$, $$b^{2}$$ and $$c^{2}$$ is $$KM^{2}$$

$$a^2+b^2+c^2=3kM^2$$

The mean of a, b and c is $$M$$.

$$a+b+c=3M$$

Squaring both sides - 

$$a^2+b^2+c^2+2(ab+bc+ca)=9M^2$$

$$3kM^2+2(0)=9M^2$$

$$k=3$$

Get AI Help?

Over 8000+ registered students have benefitted from Cracku's IPMAT Course

Crack IPMAT 2026 with Cracku

Ask AI

Ask our AI anything

AI can make mistakes. Please verify important information.