Math Statistics and Probability

According to a random telephone survey, 85% of all working adults in the U.S. are satisfied with their current job. If I asked 500 adults, how many do you predict would be satisfied with their current job?

• 85 adults

• 340 adults

• 500 adults

• 425 adults

Manny wants to know how many students at CTMS enjoy solving math problems. What is the best sampling method?

• ask for 20 volunteers to discuss whether they enjoy solving math problems

• ask the last 20 people to arrive at CTMS 

• Randomly ask 2 students in the hallway

• Ask every 20th student that walks into school

A recent survey of 800 seventh graders from across the state shows 4 out of 10 like to play paper football. How many students said they like to play paper football?

• 40 students

• 200 students 

• 320 students

• 8,000 students

If a bag contains 3 red marbles, 2 blue marbles, and 5 green marbles, what is the probability of picking a blue marble?

What is the mean of the following set of numbers: 4, 8, 12, 16, 20?

Mathematical Equivalence

ON

What is the median of the following set of numbers: 3, 7, 9, 6, and 12?

• 6

• 7

• 9

• 5

At a middle school, the 7th graders will conduct a survey for where to go on a field trip. Which method will result in the least biased decision?

• to randomly ask 8th grade students who went on a field trip last year

• to randomly choose some 7th grade students to select a location

• to ask all 7th grade teachers and administrators for a location

• to ask the student council to choose a location

In a game, the probability of winning is 1 out of 5. How many times could Lisa expect to win if she plays the game 85 times?

• 17

• 34

• 68

• 80

A coin was tossed 80 times, out of which it landed on heads 60 times. What is the relative frequency of the coin toss resulting in tails?

• 20%

• 25%

• 50%

• 75%

Kris has a bag that contains only red marbles, green marbles, and purple marbles. Kris pulls a marble from the bag, records the color of the marble and puts it back in the bag. She performs 25 pulls and draws 8 red marbles, 12 green marbles, and 5 purple marbles. Based on the data, about how many times would Kris pull a red marble if she performed 1,000 pulls?

• 200

• 320

• 330

• 470