set theory
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In a survey it was reported thatb 400 people owned fiet cars and 200 owned ambassador cars. 50 owned both fiet & ambassador cars. Determine the no. of cars that were surveyed?
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400+20050=550
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Set A is of people who own ambassadors.
n(A) = 200
Set F is of people who on fiats
n(F) = 400
It is given that n(A Intersection F) = 50
The total number of people is n(A union F)
And we know that n(A union F) = n(A) + n(F)  n(A intersection F)
=200 + 40050
= 550
Another way to look at it is when we add the number of people who own ambassadors(200) to the number of people who own fiats(400) we are counting the people who own both twice. Hence we subtract the number of people who own both once
n(A) = 200
Set F is of people who on fiats
n(F) = 400
It is given that n(A Intersection F) = 50
The total number of people is n(A union F)
And we know that n(A union F) = n(A) + n(F)  n(A intersection F)
=200 + 40050
= 550
Another way to look at it is when we add the number of people who own ambassadors(200) to the number of people who own fiats(400) we are counting the people who own both twice. Hence we subtract the number of people who own both once
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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.
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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LEARNING, APPLICATION AND TIMING IS THE FACT OF GMAT AND LIFE AS WELL... KEEP PLAYING!!!
Whenever you feel that my post really helped you to learn something new, please press on the 'THANK' button.