The average waight 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. Choices:
A) 23 KG B) 43 KG C) 21 KG D) 31 KG E) 43 KG
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 KG
<result>D</result>
The average waight 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.