Answer:
Minimum 5 socks needs to be selected.
Step-by-step explanation:
Given that there are four different colors of socks.
So, if you pick 4 socks , in worst case it will be all four of different color.
now if you pick 5th socks it will be either of those four colors.
Hence, minimum 5 socks must be taken to ensure that a pair of matching-color socks is selected.
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To elaborate it more,
let four colors be red, yellow, blue , green
if you pick 5 socks, then in worst case four will be all of different color
red, yellow, blue , green but fifth will be
- If red socks, then there will 1 pair of red socks
- If yellow socks, then there will 1 pair of yellow socks
- If blue socks, then there will 1 pair of blue socks
- If green socks, then there will 1 pair of green socks
Hence. minimum 5 socks needs to be selected.
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In general, if you have n objects of different colors then you need to take minimum n+1 number of object to have at least two object of same color.