Crazy problem solving question..
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they are asking for bread only buyers which equals neiter( C or M) buyers which equals 1-probability of M&C ONLY buyers.
C only = 50-20 =30
M only = 40-20 =20
then P (M&C) = 20+30/100 or 1/2
1-1/2 =1/2 probability of M only.
C only = 50-20 =30
M only = 40-20 =20
then P (M&C) = 20+30/100 or 1/2
1-1/2 =1/2 probability of M only.
Thanks for answereing, but the correct answer is 3/10 not 1/2. thanks again.. someone else please help me..freedsl wrote:they are asking for bread only buyers which equals neiter( C or M) buyers which equals 1-probability of M&C ONLY buyers.
C only = 50-20 =30
M only = 40-20 =20
then P (M&C) = 20+30/100 or 1/2
1-1/2 =1/2 probability of M only.
What i did wrong was take 20 off twice, anyway
So you have the formula ALL buyers that trade in M and C (Unique buyers) = M+C- both (M&C) = 50+40-20 =70 the prob for this is 70/100 or 7/10
the opossite which would be only B buyers is 1- 7/10 =3/10
So you have the formula ALL buyers that trade in M and C (Unique buyers) = M+C- both (M&C) = 50+40-20 =70 the prob for this is 70/100 or 7/10
the opossite which would be only B buyers is 1- 7/10 =3/10
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Kaching!jscoligan wrote:Cake+muffin+neither-both=Real total
50+40+neither-20=100
neither=30
30/100=> 3/10
Perfect question for the overlapping sets formula:
True # of items = # with characteristic 1 + # with char 2 + # with neither char - # with both chars
In this case:
100 = 50 + 40 + neither - 20
100 = 70 + neither
30 = neither
So, probability of finding a "neither" person is 30/100 = 3/10
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