Question 60
$$a, b, c$$ are three positive numbers, such that, $$(a + b + c) = 20, a^2 + b^2 + c^2 = 152$$. The value of $$(ab + bc + ca)$$ is equal to:
Solution
$$(a + b + c)^{2}=a^2 + b^2 + c^2+2(ab+bc+ac)$$
$$20^{2}=a^2 + b^2 + c^2+2(ab+bc+ac)$$
$$400=152+2(ab+bc+ac)$$
$$(ab+bc+ac)=\frac{248}{2}=124$$
Need AI Help?
Create a FREE account and get:
- Free SSC Study Material - 18000 Questions
- 230+ SSC previous papers with solutions PDF
- 100+ SSC Online Tests for Free
