SOLUTION: please help! In a certain school there were 5 more seniors than juniors. In one marking period, 12 percent of the juniors and 10 percent of the seniors were on the honor roll. I

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: please help! In a certain school there were 5 more seniors than juniors. In one marking period, 12 percent of the juniors and 10 percent of the seniors were on the honor roll. I      Log On


   



Question 172986: please help!
In a certain school there were 5 more seniors than juniors. In one marking period, 12 percent of the juniors and 10 percent of the seniors were on the honor roll. If the total of juniors and seniors on the honor roll was 17, how many seniors were there in the school in that marking.

Answer by Mathtut(3670) About Me  (Show Source):
You can put this solution on YOUR website!
let j and s be the number of juniors and seniors respectively
:
s=j+5....eq 1
.12j+.1s=17...eq 2
:
plug s's value from eq 1 into eq 2
:
.12j+.1(j+5)=17
:
.12j+.1j+.5=17
:
.22j=16.5
:
j=75juniors
:
highlight%28s=75%2B5=80%29seniors