Mrs. Smith's classroom can hold at the most 30 students. Her first period class had 4 boys for every 3 girls. When 3 boys and 1 girl were added to the class, the new ratio became 3 boys to 2 girls. How many total students are now in the class? Show all work and explain the process.

Answer 1

original class:
number of boys = 4x
number of girls = 3x

new class:
boys --- 4x+3
girls --- 3x + 1

(4x+3)/(3x+1) = 3/2
9x + 3 = 8x + 6
x = 3

original class
boys = 12
girls = 9 , notice ratio = 12:9 = 4:3

new class
boys = 15
girls = 10 , new ratio = 15:10 = 3:2