Algebra/Trig

The members of a men’s club have a choice of wearing black or red vests to their club meetings. A study done over a period of many years determined that the percentage of black vests worn is 60%. If there are 10 men at a club meeting on a given night, what is the probability, to the nearest thousandth, that at least 8 of the vests worn will be black?

I know you're supposed to use combinations, but how do you write it all out?

  1. 👍 0
  2. 👎 0
  3. 👁 288
  1. BINOMIAL DISTRIBUTION, yes uses Combinations

    n = 10
    probability of black = .6
    probability not black = .4

    prob 8 = C(10,8) .6^8 .4^2
    = 45*.6^8*.4^2 = .121

    prob 9 = C(10,9) .6^9 .4^1
    = 10 *.6^9 * .4 = .040

    prob 10 = C(10,10) .6^10 .4^0
    = 1 *.6^10 * 1 = .006

    sum = .121+.040+.006 = .167

    I got the Combinations from Pascal's triangle but you can use a table or calculate
    C(n,k) = n!/[ k! (n-k)! ]

    1. 👍 0
    2. 👎 0
  2. thanks!

    1. 👍 0
    2. 👎 0

Respond to this Question

First Name

Your Response

Similar Questions

  1. statistics

    The red face cards and the black cards numbered 2-9 are put into a bag. Four cards are drawn at random without replacement. Find the following probabilities: a) All 4 cards are red b) 2 cards are red and two cards are black c) At

    asked by oscar on December 12, 2010
  2. Algebra

    A club currently has 300 members who pay $ 400 per month for membership dues. The​ club's board members want to increase monthly revenue by lowering the monthly dues in hopes of attracting new members. A market research study

    asked by Janice on June 24, 2015
  3. Pre-Algebra

    A chess club with 40 members is electing a new president. Lisa received 16 votes. What percentage of the club members voted for Lisa?

    asked by Anonymous on September 18, 2016
  4. math

    The local reader’s club has a set of 36 hardback books and a set of 30 paperbacks. Each set can be divided equally among the club members. What is the greatest possible number of club members?

    asked by NUNYA on October 11, 2017
  5. math

    The mathematics club in a school has 53 members. 5/7 of the girls members and 3/5 of the boys members are from lower secondary. The total number of lower secondary members is 35. How many members of the club are boys?

    asked by Waqas on September 4, 2016
  1. math

    The mathematics club in a school has 53 members 5/7 of the girl members and 3/5 of the boys members are from lower secondary. The total numbers of lower secondary members is 35. How many members of the club are boys?

    asked by city school on September 8, 2017
  2. Math

    4 students are running for club president in a club with 50 members. How many different vote counts are possible, if all 50 members are required to vote?

    asked by Halp on December 15, 2013
  3. math

    On a certain legislative committe, 3/8 of the committee members are Republicans. If 2/3 of the members are men and 3/5 of the men are Democrats, what fraction of the members are Democratic women?

    asked by timothy on July 9, 2015
  4. PreCalculas

    1.Suppose you pay $16,000 for a new car and estimate that it will be worth 20% less with each passing year. What will your car be worth after 3 years? 2.A school club uses a telephone chain to inform members of changes in plans.

    asked by Anonymous on November 30, 2015
  5. Combination math

    The camera club has 5 members and the mathematics club has 8. There is only one member common to both clubs. In how many ways could a committee be formed with at least one member from each club?

    asked by rinchan on October 28, 2013
  6. Science

    In a particular breed of cattle, a black coat is dominant over a red coat. If a cow with a red coat is crossed with a black bull that is heterozygous for coat color, what percentage of their offspring would you expect to be black?

    asked by Steve on October 22, 2013

You can view more similar questions or ask a new question.