At a college party, 70% of the women are wearing red t-shirts. If 60% of the people at the party are wearing red t-shirts, what is the ratio of women to men at the party?
1) Forty percent of the men at the party are wearing red t-shirts.
2) There are 120 people at the party.
I think the answer is C. Please let me know.
D.S overlapping sets
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- grockit_jake
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The key here is that they are asking for the ratio of women to men. So the absolute number of each is not necessarily needed.
With Statement 1, we know:
7/10W + 4/10M = 6/10(M+W)
7W + 4M = 6M + 6W
W = 2M
W/M = 2
Again, this only tells us that the ratio of W:M is 2:1, and doesn't tell us how many of each, but the question only asks for the ratio. Statement 1 is sufficent
With Statement 2, we know:
7/10W + x/100M = 3/5(120)= 72
70W+xM = 72
M + W = 120
Since there are 3 variables and 2 equations, we can't figure it out. Namely, you can think about the variation of W's, and how the M figure could vary accordingly and still satisfy the M + W = 120 requirement. Statement 2 is insufficient.
With Statement 1, we know:
7/10W + 4/10M = 6/10(M+W)
7W + 4M = 6M + 6W
W = 2M
W/M = 2
Again, this only tells us that the ratio of W:M is 2:1, and doesn't tell us how many of each, but the question only asks for the ratio. Statement 1 is sufficent
With Statement 2, we know:
7/10W + x/100M = 3/5(120)= 72
70W+xM = 72
M + W = 120
Since there are 3 variables and 2 equations, we can't figure it out. Namely, you can think about the variation of W's, and how the M figure could vary accordingly and still satisfy the M + W = 120 requirement. Statement 2 is insufficient.
- kmittal82
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Should be (A)
Let there be M men, and W women
total people wearing red tshirt = 0.6(M+W)
We also know number of women wearing red tshirt = 0.7W
Stmt 1)
Total number of people wearing red tshirt = men with red tshirt + women with red-tshirt
=> 0.6(M+W) = 0.4M + 0.7W
Solve to get W/M = 1/2
Sufficient to answer the question.
Let there be M men, and W women
total people wearing red tshirt = 0.6(M+W)
We also know number of women wearing red tshirt = 0.7W
Stmt 1)
Total number of people wearing red tshirt = men with red tshirt + women with red-tshirt
=> 0.6(M+W) = 0.4M + 0.7W
Solve to get W/M = 1/2
Sufficient to answer the question.