The average weight of A,B,C is 45 Kg. The avgwgt of A & B be 40Kg & that of B,C be 43Kg. Find the wgt of B.	Select the correct option.
A) 23
B) 43
C) 21
D) 31
E) 43
Sol. Let A,B,c represent their individual wgts.   Then,   A+B+C=(45*3)= 
<gadget id="calculator">(45*3)</gadget>
<output>135</output>
135Kg   A+B=(40*2)= 
<gadget id="calculator">(40*2)</gadget>
<output>80</output>
80Kg &amp; B+C=(43*2)= 
<gadget id="calculator">(43*2)</gadget>
<output>86</output>
86Kg   B=(A+B)+(B+C)-(A+B+C)   =(80+86-135)= 
<gadget id="calculator">(80+86-135)</gadget>
<output>31</output>
31Kg.   ANSWER 31
<result>D</result>
The average weight of A,B,C is 45 Kg. The avgwgt of A & B be 40Kg & that of B,C be 43Kg. Find the wgt of B.