Making Predictions

  1. A baseball player reaches base 35% of the time. How many times can he expect to reach base in 850 at-bats?
  2. Angela can make 65% of her shots from the free-throw line. If she shoots 75 times, how many shots can she expect to go in?
  3. In 1951, Odessa, Texas had temperatures of at least 95° F 11% of the time. During that year, how many days could residents predict would have highs of at least 95° F?
  4. A survey shows that 67% of peanut butter lovers prefer chunky-style. Out of 850 people surveyed, how many can be predicted to say they prefer chunky-style peanut butter?

Make a prediction based on a theoretical probability.

  1. Gil rolls a number cube 78 times. How many times can he expect to roll an odd number greater than 1?
  2. Jenna flips two pennies 105 times. How many times can she expect both coins to come up heads?
  3. A shoebox holds same-size disks. There are 5 red, 6 white, and 7 blue disks. You pick out a disk, record its color, and return it to the box. If you repeat this process 250 times, how many times can you expect to pick either a red or white disk?
  4. Ron draws 16 cards from a standard deck of 52. The deck is made up of equal numbers of four suits—clubs, diamonds, hearts, and spades. How many of the cards drawn can Ron expect to be spades?

Solve each problem.

  1. During February and March, Jack is spending 7 days in the Yukon to check on endangered species. The region has snowfall that blocks roads 20 days during these months. Can Jack expect to be able to get around at least 5 of the days? Explain.
  2. ABC Airlines has had delays on 18 of 126 recent flights. DEF Airlines has had delays 13% of the time. Which airline would you expect to provide more reliable service? Why? ________________________________________