In an institute, 60% of the students are boys and the rest are girls. Further 15% of the boys and 7.5% of the girls are getting a fee waiver. If the number of those getting a fee waiver is 90, find the total number of students getting 50% concessions if it is given that 50% of those not getting a fee waiver are eligible to get half fee concession?
Choose the correct choice from the following:
A) 360
B) 280
C) 320
D) 330
E) 350
Solution: Let us assume there are 100 students in the institute.   Then, number of boys = 60   And, number of girls = 40   Further, 15% of boys get fee waiver = 9 boys   7.5 % of girls get fee waiver = 3 girls   Total = 12 students who gets fee waiver   But, here given 90 students are getting fee waiver. So we compare   12 = 90   So, 1 = 90/12= 
<gadget id="calculator">90/12</gadget>
<output>15/2 = around 7.5</output>
7.5   Now number of students who are not getting fee waiver= 51 boys and 37 girls.   50% concession = 25.5 boys and 18.5 girls (i.e. total 44).   Hence, required students = 44*7.5= 
<gadget id="calculator">44*7.5</gadget>
<output>330</output>
330.   Answer: Option 330
<result>D</result>
In an institute, 60% of the students are boys and the rest are girls. Further 15% of the boys and 7.5% of the girls are getting a fee waiver. If the number of those getting a fee waiver is 90, find the total number of students getting 50% concessions if it is given that 50% of those not getting a fee waiver are eligible to get half fee concession?