Initially, 40% of the students at the school dance are freshmen. Then, 15 more freshmen arrive, after which 50% of the students at the dance are freshmen. How many students are now at the dance after the additional freshmen arrive?
+36916 x = initial amount of people at the dance and
Initially .40 x = freshmeno
then add 15 freshmen
.50 (x+15) = freshmeno + 15
.50(x+15 ) = .40x + 15
.5x + 7.5 = .40x + 15
.1x = 7.5
x = 75 people at the dance initially ..... after 15 more freshmen arrive there is 90 people at the dance
