math - gr 12

posted by .

the social convenor has 12 volunteers to work at a school dance. Each dance requires 2 volunteers at the door, 4 volunteers on the floor, and 6 floaters. Joe and Jim have not volunteered before so the soicial convenor does not want to assign them to work together. In how many ways can the volunteers be assigned?

the answer is 9240, but i don't understand how to get that, help please??!

  • math - gr 12 -

    Break it up into 3 cases
    1. Joe at the door, then 10 others at the door, C(10,4) on the floor, C(6,6) as floaters
    = 10x210x1 = 2100
    2. Joe on the floor, leaving C(10,3) for the remainder on floor, C(8,2) for the door and C(6,6) as floaters
    = 120x28x1 = 3360
    3. Joe as floater leaving C(10,5) for the remaining floaters, C(6,4) for the floor, and C(2,2) for the door
    = 252x15x1 = 3780

    total = 2100+3360+3780 = 9240

  • math - gr 12 -


  • math - gr 12 -


Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. English

    Where did you volunteer? 1. I volunteered at the Nakdong River. I picked up trash on the seashore with other volunteers. I collected plastic bottles and other things from the river. The river has become cleaner with our work. 2. I
  2. English

    What kind of work is done by volunteers? 1. To help the handicapped to take baths and have meals. 2. To take care of children in/at orphanages. 3. To care for sick people/patients at hospitals. 4. To clean dirty places such as rivers,
  3. English

    1. The volunteers there deliver food to old people. (What is the part of speech of 'there'?
  4. math

    Ned is one of 6 library volunteers. He is also one of 8 playground volunteers. Each week 1 volunteer from each group is randomly chosen from each group to work. (Park A) What is the probability that Ned will be chosen for both groups …
  5. Liberal Arts

    Part 1: You finally made it…graduation day has arrived! Your parents are so proud that they are throwing you a HUGE party. They have rented a big tent for your graduation party just in case it rains. The inside of the tent (represented …
  6. Psychology

    What is the independent variable in this scenario: A research Psychologist is working in a federal prison and is asked to asses this new program. From 70 inmate volunteers, the psychologist randomly assigns 45 inmate volunteers to …
  7. English

    Write the complete subject and underline the simple subject., 1/ The gourds' noise sounds like dry leaves in the wind. Answer:cmplete subject : the gourds'noise sounds Simple subject: sounds 2/ Martin's friend come some times and plays …

    The staff of the Westpoint Public Library signed up 6 volunteers in the last 21 days. If the library staff continues to sign up volunteers at this rate, how many new volunteers will they get in the next 7-day week?
  9. math

    in a class of 21 students, 1 out of every 3 students volunteer to work. What is the ratio of volunteers to non volunteers?
  10. Math

    The table shows the number of volunteers that work at a radio-thon for different numbers of hours . How many volunteers can be expected to go to work for 9 hours?

More Similar Questions