A sum of money lent at compound interest for 2 years at 20% per annum would fetch Rs 482 more, if the interest was payable half-yearly than if it was payable annually. The sum is: (a) Rs 10,000 (b) Rs 20,000 (c) Rs 40,000 (d) Rs 50,000

Options

A. 0.07
B. 0.13
C. 0.15
D. 0.22

Answer

C

Explanation

Number of students in the college =7200
Number of boys `=(7)/(12)xx7200=4200`
Number of girls `=(5)/(12)xx7200=3000`
Number of student in B.Tech. (nano techonology)
=22% or 7200=1584
Number of girls in B. Tech. (computer science)
=16% of 3000=480
Number of boys in B.Tech.(mechanical)= =18% of 4200 =630
Number of girls in B.Tech. (civil) =30% of 480 =144
Number of boys in B.Tech. (electronics)=15% of 4200 =630
Number of boys in B.Tech. (computer science) =50% or 180=240
Number of gifls in B.Tech. aerospace) 15% of 3000 = 45000
Number of boys in B.Tech (civil) `=(3)/(1)xx144=432`
Number of students in B.Tech (electronics) 24% of 72000 =1728
`:.` Number of girls in B.Tech. (electronics)= 1728-630 =1098
Number of boys in B.Tech (aerospace) =`(12)/(5)xx450=1080`
Number of boys in B.Tech(nano technoloy) = Remaining
Number of boys =4200-(750+630+240+432+1080)
=4200-3138=1062
`:.` Number of girls in B.Tech (mechanical) = Remaining
Number of girls =3000-(480+144+450+1098+522)
= 3000-2694=306
Tablular form of above information is whon below.

Number of girls enroled in B.Tech (electronics) =1098
`:.` Required percentage `=(1098)/(7200)xx100%`
`=15.25~~15%`