Question

connor and lily are making bags of trail mix. connor puts 7 pretzels in each bag and lily puts the same unknown number of raisins, r, in each bag. after filling 3 bags, they have used 45 items. write an equation to represent the scenario.

Explanation:

Step1: Define items per bag

Each bag has $7 + r$ items.

Step2: Total items for 3 bags

Multiply per-bag items by 3, set equal to 45.
$$3(7 + r) = 45$$

Answer:

$3(7 + r) = 45$