Amir is making bag lunches for a group of 5 friends to take on a day trip to a museum. Each person will get one sandwich and some snacks. He places 20 items total in the bags. To determine the number of snacks in each bag, he first divides 20 by 5, and then he subtracts 1.

Question

Which equation could Amir have used to help him correctly solve this problem?
Responses
5s + 1 = 20
5(s − 1) = 20
5s − 1= 20
5(s + 1) = 20

Answer 1

To determine the number of snacks in each bag, Amir wants to find out how many snacks there are after he sets aside sandwiches for each friend. Given that each person receives one sandwich, he is left with \(20 - 5\) items for snacks.

Let \(s\) represent the number of snacks each friend receives. Since there are 5 friends, the total number of snacks can be represented as \(5s\). Amir knows that he has 20 items in total (which includes both the sandwiches and snacks).

The equation can be set up as follows:

1. He first assigns 1 sandwich per person (total of 5 sandwiches), which accounts for 5 items.
2. The remaining snacks amount to \(20 - 5 = 15\).
3. This gives the equation: \(5s = 15\).

However, since Amir initially divides 20 by 5 and then subtracts 1, he effectively sets up his equation to find the correct number of snacks per bag after considering the one item per bag subtracted.

Thus the correct equation representing this setup is:

\[ 5(s + 1) = 20 \] This equation accounts for the sandwiches (1 each) and finds the remaining total of items left for snacks.

The answer is:

5(s + 1) = 20