The average weight of A, B and C is 45 kg. If the average weight of A and B be 40 kg and that of B and C be 43 kg, then the weight of B is:  Choose the correct choice from the following answers:
A) 31 B) 35 C) 32 D) 38 E) 40
A + B + C = (45 * 3)= 
<gadget id="calculator">(45 * 3)</gadget>
<output>135</output>
135 --- (i)   A + B= (40 * 2)= 
<gadget id="calculator">(40 * 2)</gadget>
<output>80</output>
80 --- (ii)   B + C= (43 * 2)= 
<gadget id="calculator">(43 * 2)</gadget>
<output>86</output>
86 --- (iii)   Adding (ii) and (iii), we get: A + 2B + C= 166 --- (iv)   Subtracting (i) from (iv), we get: B = 31   B's weight = 31 kg.   31NSWER 31
<result>A</result>
The average weight of A, B and C is 45 kg. If the average weight of A and B be 40 kg and that of B and C be 43 kg, then the weight of B is: