Reworded Question: You have $30. You need to buy 1 sandwich and drink for yourself and two friends. Using the remaining money, what is the least and greatest number of snacks you can buy.
You first have to buy 1 sandwich and drink for 3 people, including yourself. So you need to buy 3 sandwiches and 3 drinks total.
For the situation where you can buy the least amount of snacks, you are buying the most expensive drink and sandwiches- so then you have less money to spend on snacks.
The most expensive sandwich is roast beef for $7 and the most expensive drink is a large for 2 dollars.
Calculate the cost by multiplying it by 3, because you need three each for yourself and 2 friends
3 * $7 + 3 * $2 = $21 + $6 =
$27 for the sandwiches and drinks
You have $30, so when you subtract the cost of the expensive sandwiches and drinks
$30 - $27 = $3
You only have $3 left. The most expensive snack on the menu is a brownie for $3- so you should buy 1 brownie to get the least number of snacks vs. you buying 3 pretzels, because you want to least amount of snacks.
The least number of snacks is 1.
Now going back, we need to calculate the greatest number of snacks
For this situation, you need to buy the cheapest drink and sandwiches- so then you have more money to spend on snacks.
The least expensive sandwich is veggie for $4 and the least expensive drink is a small for $1.
Calculate the cost by multiplying it by 3, because you need three each for yourself and 2 friends
3 * $4 + 3 * $1 = $12 + $3 =
$15 for the sandwiches and drink for the inexpensive sandwiches and drinks
You have $30, so subtract how much you spent on sandwiches and drinks
$30 - $15 = $15
You have $15 left. The least expensive snack on the menu is a pretzel for $1- so you should buy as many pretzels as you can, because you want to most amount of snacks. You can buy 15 pretzels with $15.
The greatest number of snacks is 15.
Explanation-
I kinda explained everything already, but to sum it up.
The least number of snacks is 1.
To buy the least amount of snacks, you need to spend the most money on drinks and sandwiches and buy expensive snacks so you can't afford as many.
The greatest number of snacks is 15.
To buy the most  snacks, you need to buy the cheapest drink and sandwiches so you have a lot of money left over. Then, buy the least expensive snacks, so you can buy a lot.
