John has 10 pairs of matched socks. If he loses 5 individual socks, what is the greatest number of pairs of matched socks he can have left?
Choose one:  A) 8  B) 7  C) 5  D) 4  E) 3
Because we have to maximize the pair of matched socks, we will remove 2 pairs(4 socks) out of 10 pairs 1 sock from the 3th pair.   Thus the no of matching socks pair remaining = 10 - 3= 
<gadget id="calculator">10 - 3</gadget>
<output>7</output>
7   Answer 7
<result>B</result>
John has 10 pairs of matched socks. If he loses 5 individual socks, what is the greatest number of pairs of matched socks he can have left?