Data Sufficiency

S7-25 A total of 774 doctorates in mathematics were granted to United States citizens by American universities in the 1972-1973 school year, and W of these doctorates were granted to women. The total of such doctorates in the 1986-1987 school year was 362, and w of these were granted to women. If the number of doctorates in mathematics granted to female citizens of the United States by American universities decreased from the 1972-1973 school year to the 1986-1987 school year, was the decrease less than 10 percent?

1. 1/10 < W/774 < 1/9
2. W = w + 5

Answer is C

from A you get the range of W

77.4 < W < 86

from B we get the delta i.e W-w = 5

so the % change will be 5 x 100 /W

since, we know that W > 50 so the % decrease will be less than 10% for the given range of W (from A)

Didnt get it, can you elaborate, please?

Hi

The answer can be B- as B itself provides the answer as to whether the reduction is less then 10%.

If W-w=5 ,so the % reduction is 5/774*100 , which is less then 10%, so B itself is sufficient.

In such cases if we use B also and use A along with it, considering the fact that B alone can solve this, would answer still be C.

Pls Clarify

Your assumption is not correct.

774 = M + W

where M = PHD assigned to men and W = phd assigned to women

in case, W = 10

then the % change will be (5/10) x 100 = 50%

so A is required to know the range of W

thanks netigen, i overlooked a very basic requirement

thanks for correcting