manhatten review gmat math study guide - data sufficiency

[nickhar130]

9. At the time of admission, 35 percent of all doctorate students at a particular business school have a Ph.D in a non-business related field. Meantime, 45 newely admitted students have a master's degree as their highest degree. Exactly how many Ph.D. students are there at this business school based on the following statistics at the time of admission for the entire program?

1) 35 have a doctorate degree completed in a non-business related field.

2) 45 percent have a master's degree as their highest degree


Can someone please break this down for me. I feel this should be a easy question.

[Night reader]

9. At the time of admission, 35 percent of all doctorate students at a particular business school have a Ph.D in a non-business related field. Meantime, 45 newely admitted students have a master's degree as their highest degree. Exactly how many Ph.D. students are there at this business school based on the following statistics at the time of admission for the entire program?

1) 35 have a doctorate degree completed in a non-business related field.

2) 45 percent have a master's degree as their highest degree


Can someone please break this down for me. I feel this should be a easy question.

This must the very easy question - at 300-400 level...

Call S-PhD Students, D-Students who completed their Doctorates, M-Students with Master's degrees

S=0.35*S(%D)+M(45)

st(1) 0.35*S (%D) corresponds to 35, find S=35/0.35, S=100 Sufficient;
st(2) 45% of S corresponds to M(45), find 45=0,45*S (proportion of M within S), S=100 Sufficient;

Pick D.