Question

Which of the following is a combination?1. Student council has 23 members. They are choosing a president, vice-president, and treasurer. How many different ways can the three positions be filled?2. Fifteen students are running the mile race for field day at school. The first three finishers will get a blue (1st), red (2nd), and yellow (3rd) ribbon. How many ways are there for the students to win the ribbons?3. Suzy is packing for a family trip to Hershey Park. She has 30 T-shirts in her closet and needs to choose 4 to take on vacation. How many possible ways are there for her to choose the 4 shirts?4. The lock on a safe requires a three letter code to unlock. How many codes are possible?

Answer 1

Answer: Combination – 3. Suzy is packing for a family trip to Hershey Park. She has 30 T-shirts in her closet and needs to choose 4 to take on vacation. How many possible ways are there for her to choose the 4 shirts?

Step-by-step explanation

• Combination,: a way of selecting items from an arrangement where the ,order, of the selection ,does not matter.

The first option is choosing a president, vice-president, and treasurer. Thus, the order in which the selection of 3 over the 23 are selected is important.

The second option also takes into consideration the order in the selection, as the 1st, 2nd, and 3rd place will get different ribbons.

The third option says that Suzy has 30 T-shirts and needs to choose 4. In this case, the order does not matter, as she will take 4 and the 1st one she chooses is not different from the last in terms of places.

Finally, the fourth option needs to take into consideration the order, as the password for the lock needs an order in the numbers to unlock.