In a survey of 1000 customers, the number of
people who buy various grades of coffee seeds were
found to be as follows:
A grade only - 180: A grade but not B grade - 230;
A grade and C grade • 80. A grade - 260, C grade
480; C grade and B grade - 80; None of the three
grades 240
How many buy C grade, if and only if, they
do not buy B grade?
Answers
Answer:
Step-by-step explanation:
Given : a survey of 1000 customers revealed the following in respect of their buying habits of different grades a grade only =180 a and c grade =80 c grade =480 a grade but not b grade =230 a grade =360 c and b grades =80 none=140
To find : how many Buy B grade
Step-by-step explanation:
Total Customers = 1000
A grade only = 180
A & C grade A∩C = 80
C grade C = 480
A Grade but not B grade = 230
A grade A = 360
B & C Grades B ∩C= 80
None = 140
like all Grades = A∩B∩C
A Grade but not B grade = A only + A∩C - A∩B∩C
=> 230 = 180 + 80 - A∩B∩C
=> A∩B∩C = 30
A only = A - A∩B - A∩C + A∩B∩C
=> 180 = 360 - A∩B - 80 + 30
=> A∩B = 130
Total = A + B + C - A∩B - B∩C - A∩C + A∩B∩C + None
=> 1000 = 360 + B + 480 - 130 - 80 - 80 + 30 + 140
=> B = 280
280 Buy B Grade
Learn More:
In a class of 140 students, 60 play football, 48 play hockey and 75 ...