The students at Fillmore Middle School had the following choices for lunch on Monday:

Sandwich: roast beef or sliced turkey
Salad: cole slaw or fruit salad
Dessert: white cake or sugar cookie
Beverage: white or chocolate milk

Make a tree diagram of the possible lunch combinations the students had to choose from.

Using the tree diagram from problem 1, what is the probability that a student will choose a combination that includes a roast beef sandwich, a sugar cookie, and chocolate milk?

1 answer

Tree diagram:

Sandwich: roast beef, sliced turkey
- Roast beef:
- Salad: cole slaw, fruit salad
- Dessert: white cake, sugar cookie
- Beverage: white milk, chocolate milk
- Dessert: white cake, sugar cookie
- Beverage: white milk, chocolate milk
- Salad: cole slaw, fruit salad
- Dessert: white cake, sugar cookie
- Beverage: white milk, chocolate milk
- Dessert: white cake, sugar cookie
- Beverage: white milk, chocolate milk

Total possible combinations: 2 (roast beef sandwich) x 2 (salad choices) x 2 (dessert choices) x 2 (beverage choices) = 16

Probability of choosing roast beef sandwich, sugar cookie, and chocolate milk = 1/16 = 0.0625 or 6.25%