In a certain school, the ratio of boys to girls is 7 : 5. If there are 2400 students in the school, then how many girls are there in the school?

Options

A. `187.5%`
B. `200%`
C. `212.5%`
D. `225%`

Answer

D

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 boys enrolled in B.Tech. (aerospace) =1080
Number of girls enrolld in B.Tech. (computer science) =480
`:.` Required percentage `=(1080)/(480)xx100%=225%`