Sum of the squares of 3 no.'s is 138 and the sum of their products taken two at a time is 131. Find the sum?	Choose the most appropriate option.
A) 20 B) 24 C) 26 D) 28 E) 30
(a + b + c)2 = a2 + b2 + c2 + 2(ab +bc + ca) = 138 + 2* 131   a + b + c = √400 = 20   20
<result>A</result>
Sum of the squares of 3 no.'s is 138 and the sum of their products taken two at a time is 131. Find the sum?