1. CoinFrequency Quarters7 Dimes13 Nickels8 Pennies12 Determine the probability that the coin she pulled to give to her sister was worth less than $0.25. A) 17.5%B) 20%C) 33%D) 82.5% $.25 is the value of a quarter…less than that includes all the other coins. 13+8+12=33 coins. There are 40 coins altogether. 33/40=.825.825=82.5%

2. CoinFrequency Quarters4 Dimes13 Nickels7 Pennies6 Determine the probability that the coin she pulled to give to her sister was worth more than than $0.05. Express your answer as a decimal rounded to the nearest hundredth if necessary. $.05 is the value of a nickel…more than that includes the dimes and quarters. 13+4=17 coins. There are 30 coins altogether. 17/30=.57

3. Bob tried a new skateboard trick 40 times. Bob was only able to perform the new trick 3 times successfully. According to this data, what is the probability that Bob will be unsuccessful the next time he tries this trick? Express your answer as a percent rounded to the nearest whole percent. There were 3 successful tries out of 40 tries altogether. The rest were unsuccessful, so 40-3=37 unsuccessful tries. 37/40=.925.925=92.5% Rounded to the nearest WHOLE is 93%

4. Bob tried a new skateboard trick 60 times. Bob wasn’t able to do the trick 12 of the times. According to this data, what is the probability that Bob will be successful the next time he tries this trick? Express your answer as a percent rounded to the nearest whole percent. There were 12 unsuccessful tries out of 60 tries altogether. The rest were successful, so 60-12=48 successful tries. 48/60=.8.8=80%

5. Susan will roll a number cube one time and will select one card from a group of four cards each containing one letter from the word MATH. Find the probability of Susan rolling a four and pulling the card with the letter H on it. Express your answer as a fraction in simplest form. There is one 4 out of six faces on a cube. The probability of rolling a four is 1/6. There is one H out of four cards. The probability of choosing an H is ¼ Multiply the two together 1/6*1/4=1/24

6. Susan will roll a number cube one time and will select one card from a group of four cards each containing one letter from the word MATH. Find the probability of Susan rolling a 5 and pulling the card with a T or an H on it. Express your answer as a fraction in simplest form. There is one 5 out of six faces on a cube. The probability of rolling a four is 1/6. There is one T and one H out of four cards. The probability of choosing a T or H is 2/4. Multiply the two together 1/6*2/4=2/24 Simplify 2/24=1/12

7. There are 6 boys and 4 girls on a bus. 3 of the boys are wearing glasses, and 3 of the girls are wearing glasses. One boy and one girl will be selected from the bus at random. What is the probability that the boy and girl selected will both be wearing glasses? Express your answer as a decimal rounded to the nearest hundredth. There are 6 boys and 3 of them are wearing glasses. The probability that the boy selected will wear glasses is 3/6. There are 4 girls and 3 of them are wearing glasses. The probability that the girl selected will wear glasses is 3/4. Multiply the two together. 3/6*3/4= 9/24 9/24=.375 which rounds to.38

8. There are 10 boys and 8 girls on a bus. 4 of the boys are wearing glasses, and 3 of the girls are wearing glasses. One boy and one girl will be selected from the bus at random. What is the probability that the boy and girl selected will both be wearing glasses? Express your answer as a decimal rounded to the nearest hundredth. There are 10 boys and 4 of them are wearing glasses. The probability that the boy selected will wear glasses is 4/10. There are 8 girls and 3 of them are wearing glasses. The probability that the girl selected will wear glasses is 3/8. Multiply the two together. 4/10*3/8= 12/80 12/80=.15

9. A bag contains 18 marbles. 10 of the marbles are red, 6 are blue and 2 are green. One marble will be drawn from the bag at random. Find the probability of choosing a red or blue marble. Express your answer as a fraction in simplest form. There are 18 marbles altogether. If you add the red and blue there are 16.. 16/18 simplifies to be 8/9

10. A bag contains 24 marbles. 8 of the marbles are red, 11 are blue and 5 are green. One marble will be drawn from the bag at random. Find the probability of choosing a blue or green marble. Express your answer as a fraction in simplest form. There are 24 marbles altogether. If you add the green and blue there are 16.. 16/24 simplifies to be 2/3

11. Mike spun the spinner shown at right 10 times. The results of his spins are shown below: R R B R B R B B R R According to Mike’s spins, what is the probability the result of a spin will be an R? Express your answer as a fraction in simplest form. Explain! How does the results of Mike’s spins compare to the theoretical probability of obtaining an R on a single spin? R B B B There are 6 R’s out of 10 spins. The probability of an R is 6/10. That simplifies to 3/5 On the spinner there is only 1 R out of 4 sections. The theoretical probability of an R is 1/4 The theoretical probability is much lower than what Mike found with his spins.

12. Mike spun the spinner shown at right 12 times. The results of his spins are shown below: R Y R G Y R G Y R R R Y According to Mike’s spins, what is the probability the result of a spin will be an G? Express your answer as a fraction in simplest form. Explain! How does the results of Mike’s spins compare to the theoretical probability of obtaining an G on a single spin? R Y G G There are 2 G’s out of 12 spins. The probability of an G is 2/12. That simplifies to 1/6 On the spinner there are 2 G’s out of 4 sections. The theoretical probability of an G is 2/4= 1/2 The theoretical probability is much higher than what Mike found with his spins.