John has 10 pairs of matched socks. If he loses 13 individual socks, what is the greatest number of pairs of matched socks he can have left?  Options:
A) 7	B) 3	C) 5	D) 4	E) 1
Because we have to maximize the pair of matched socks, we will remove 6 pairs(12 socks) out of 10 pairs 1 sock from the 7th pair.   Thus the no of matching socks pair remaining = 10 - 7= 
<gadget id="calculator">10 - 7</gadget>
<output>3</output>
3   Answer 3
<result>B</result>
John has 10 pairs of matched socks. If he loses 13 individual socks, what is the greatest number of pairs of matched socks he can have left?