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2019-04-22_09-42-03.jpg [ 36.84 KiB | Viewed 175 times ]
Let the total number of women surveyed be 100.
80% use at least one of the three brands. So 20% use no brand. From the above fig, we need to find the value of d+e+f+20 (use two products or all).
a + d + e = 20
b + d + f = 40
c + e + f = 10
Adding all the three equations,
a + b + c + 2(d + e + f) = 70 ________________ (1)
a + b + c + d + e + f + 20 = 80
a + b + c + d + e + f = 60 _________________ (2)
Substituting eq (1) in eq (2),
70 - 2(d + e + f) + (d + e + f) = 60
70 - (d + e + f) = 60
d + e + f = 10
We have to find the value of d+e+f+20 --> 10 + 20 => 30.
So 30 out of 100 women surveyed use 2 or 3 products.
OPTION:
D
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2019-04-22_09-42-03.jpg [ 33.27 KiB | Viewed 175 times ]
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Regards,
Chaitanya
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