Answer:
$1.25
September
$30
Step-by-step explanation:
Let's take this a step a time.
First we need to find how much the price of the flowers were in September.
We know that each flower cost $1.50 on October.
The October price was a 20% increase of the September price.
To calculate for the price of the flowers on September, we can solve it like this:
Let x = Price during September
1.2x = 1.50
We used 1.2 because the price of $1.50 is 120% of the original price.
Now we divide both sides by 1.2 to find x.
x = 1.25
The price of the flowers during September was $1.25 each.
Now the 7th grade class earned 40% of the selling price of each flower.
40% = 0.40
To find how much they made on each month, we simply multiply the percentage to the price and the number of flowers sold.
September = 0.40 x 1.25 x 900
September = 0.5 x 900
September = $450
Now for October.
October = 0.40 x 1.50 x 700
October = 0.6 x 700
October = $420
The 7th Graders earned more on September.
They earned $30 more on September than October.