Answer:
Part A: Let the September price be x, then
1.2x = 1.5
x = 1.5/1.2 = 1.25
Therefore, September price is $1.25
Part B: In September, they earned 0.4 * 1.25 * 900 = $450
In October, they earned 0.4 * 1.5 * 700 = $420
Therefore, they earned more money in September.
Step-by-step explanation: