I believe that the following represents the intent of the problem:
oquiella wrote:42. In a class, 30% of the students are girls, and 70% of these girls are intelligent. What percentage of the boys in the class are intelligent?
(1) 42% of the class is intelligent.
(2) The number of girls who are intelligent is the same as the number of boys who
are intelligent.
Let the total number of students = 100.
Thus:
Total girls = 30% of 100 = 30, implying that total boys = 100-30 = 70.
Intelligent girls = 70% of 30 = 21.
Statement 1:
Total intelligent = 42% of 100 = 42.
Intelligent boys = (total intelligent) - (intelligent girls) = 42-21 = 21.
Of the 70 boys, the percentage who are intelligent = (intelligent boys)/(total boys) * 100 = 21/70 * 100 = 30%.
SUFFICIENT.
Statement 2:
Intelligent boys = intelligent girls = 21.
Of the 70 boys, the percentage who are intelligent = (intelligent boys)/(total boys) * 100 = 21/70 * 100 = 30%.
SUFFICIENT.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at
[email protected].
Student Review #1
Student Review #2
Student Review #3