john has 10 pairs of matched socks . if he loses 9 individual socks , what is the greatest number of pairs of matched socks he can have left ?
"because we have to maximize the pair of matched socks , we will remove 4 pairs ( 8 socks ) out of 10 pairs 1 sock from the 5 th pair . thus the no of matching socks pair remaining = 10 - 5 = 5 answer c"
subtract(10, const_3)