At a party at the middle school over on Third Avenue next to the bank, 60% of the students are seventh graders. These students are joined by 20 more eighth graders, all of whom like to dance. The party is now 58% seventh graders. How many students are now at the party?

Guest Mar 25, 2021

#1**+1 **

Call the original number of students, S...and the number of girls = .60S

Total students after 20 boys arrive = S + 20

Also:

Number of girls divided by total number of students = 58%

.6S / ( S + 20 ) = .58 multiply both sides by S + 20

.6S = .58( S + 20 )

.6S = .58S + 11.6 subtract .58S from both sides

.02S = 11.6 divide both sides by .02

S = 11.6 / .02 = 580

So...the total number of students = 580 + 20 = 600

WillBillDillPickle Mar 27, 2021