Final answer:
By subtracting the amount given by Jimmy's mom from his total birthday money and then dividing by the number of cards, we found out that each card contains $25.
Step-by-step explanation:
To determine the amount of money in each of the seven cards that Jimmy received for his birthday, we need to set up an equation. First, we subtract the amount given by his mom from the total amount of birthday money he received.
So, if total money = $300 and money from mom = $125, then the money from the cards is total money - money from mom = $300 - $125 = $175.
Now, let x represent the amount of money in each card. Since there are 7 cards with the same amount of money, we can write the equation as:
7 * x = $175
Dividing both sides of the equation by 7 gives us:
x = $175 / 7
x = $25
So, each card contains $25.