Vookeh dyzynah
Dude there is a formula in Sets i.e
n(A) + n(B) - n(A intersection B) = n(AUB) i.e the total people surveyed...
When you put the values of the question in the above formula, you get the answer as 550
Intersection is referred to as common between both parameters i.e A and B.
You are new to this site right? Welcome to BTG, and I would recommend you to go through some basic concepts before solving sums...
In case of any queries, you could always PM me...
Hope I helped you, Thank You.
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