Tamara paid $3.00 for cartons of milk. Teo paid $3.75 for a different number of cartons at the same store. How much is one carton? How many cartons did each person buy?

1 - Price of each carton:

Since they both bought different number of cartons of milk from the same store, we can simply find the price of one carton from the difference between what they both paid.

Since Tamara paid 3$ and Toe paid 3.75$, we can simply say that one carton of milk costs 0.75$ and that Toe bought one carton more than Tamra.

2 - How many cartons each bought:

Tamra bought : 3 / 0.75 = 4 cartons

Toe bought : 3.75 / 0.75 = 5 cartons