# Assignments and what's happening

• Periods 1 and 5  -  Discrete Math

This is where I will post my daily message and assignment each morning by about 9:30

My e-mail: wszelingoski@hamilton.k12.nj.us

Tuesday June 9th

Just want to clarify the return of materials.  Seniors have pickup times and dates available now on the HHW website.  Everyone else's opportunities to return books and calculators will be announced in the next few weeks, so keep checking the website.

I want to congratulate the seniors on graduating and thank all of you for a good year, despite how it ended.  Feel free to e-mail me if you need anything or stop by the same room for a visit next year.

Thank you,

Mr. Ski

Announcement

I need everyone to return their textbooks and calculators on their assigned day to the school.  Your name must be on everything you return.  Obligations will be submitted for any unreturned items and a bill will be issued.  See the district website for your designated time and date.

Monday June 1st

OK here's the quiz.  Seniors, I have to have your grades wrapped up by Thursday so keep that in mind.

1)  A 6-sided die numbered 1 to 6 is rolled 10 times.  What is the probability that we will roll a 4 exactly 9 times ?

Four percent of the items coming off an assembly line are defective.  If 10 items are selected, what is the probability that:

2)  exactly 2 are defective?

3)  at most 2 are defective?

4)  none are defective?

5)  no more than 3 are defective?

Thursday May 28th

I will be posting the last quiz of the year on monday.  The assignment today is page 441 #34-41

Tuesday May 26th

using the binomial probability function on the calculator (or the formula if you want) try problems 29, 30, 31, 32 on page 440

Remember binomcdf is for alot of values but it goes down.  So binomcdf (10, .7, 6) is for probability that I succeed 6 times or less in 10 attempts if p=.7

Wednesday May 20th

page 440 problems 1-23 (odds)

This is about binomial probability.  Number of successes (k) in a certain number of trials (n) with a certain success rate (p) and failure rate (q)

there is a formula on the top of page 435, but we used the binompdf on the calculator.  It's under 2nd VARS # 0 remember, though you have to put the probability number in the middle regardless of where is it is in the book.  So #1 would be binompdf(7, .2, 4) The order is binompdf (n, p, k)

Monday May 18th

continuation of last lesson on tree diagrams

page 431 problems # 31, 33, 35, 36

make the tree diagram first.  Ask yourself what happens first?

Wednesday May 13th

today's assignment is on page 430 #15-22

The information in these problems should guide you to make a tree diagram

#15 and 19 go together and so on.

Monday May 11th

OK new chapter and probably the last chapter.

The pages to read are 421-429.  This is about Bayes' Formula which you would know better as tree diagrams.  Another familiar topic.  The assignment is on page 430 # 1-14 all based on that tree diagram.  So let me show you #1 and #9 to remind you about the difference between the conditional probabilities.  #1 says P(E/A) and #9 is P(A/E), same letters, different order.

#1 first:  the given event that we know has happened is A (always 2nd letter).  If we know we are on A, that means we know where we entered the tree (at the top) so we just bypass that and go straight to E which says .4 done

#9 is the opposite, we know E has happened.  That doesn't tell us where we are on the tree.  There are 3 different places we could have ended up on E so we need all of them.

It was either .3 x .4 or .6 x .2 or .1 x .7  Change the or's to + and that is your denominator (bottom) .  Your numerator is whichever of these same numbers came from A so that would be .3 x .4 that is your numerator (top).  so that would be (.3 x .4)  /   (.3 x .4. +  .6 x .2  +  .1 x .7) which is .12 / .31 = .387

So basically you can do 2-6 the same as #1

you can do 10 -14 the same as #9

# 7 and 8 are not conditional.  They are like just the denominator calculation from above ( so # 7 is .31) (All the combinations of how to get to E)

So I've given you a few answers, you try the rest, let me know if there's any trouble.

Wednesday May 6th

So here's the test, remember to show whatever work you can

If P(E) = 0.4 and P(F)= 0.5 and P(E∩F) = 0.2

1) what is P(EuF) ?

2) what is P(E/F) ?

3) are E and F mutually exclusive ? why?

4) are E and F independent ? why?

Two cards are drawn from a deck of cards without replacement.  The first card is looked at, then removed, then the second is drawn.

5) what is the probability that both cards are kings?

6) what is the probability that both cards are black?

7) what is the probability that the second card is a 10 given that the first card was the queen of clubs?

Monday May 4th

I'm going to let today be a review day.  I have already assigned all the review problems. so finish them, go over them, ask questions, whatever you need to do.  I will be posting a chapter 7 test on Wednesday.

Friday May 1st

today we are finishing the review pages 416-417. # 27, 29, 37, 39, 40, 41, 43

Thursday April 30th

continue your review with problems 20-26 on page 415

Test will be posted next week

Wednesday April 29th

Continue the chapter review with pages 414-415  # 4, 13, 14, 15, 17, 18, 19

Tuesday April 28th

Today we will start a review of the chapter.  Pages 413-414. #2-8 true/false and #1-4 Fill in the blank

Planning on doing the test next week

Monday April 27th

today's assignment is on independent events like we were doing last week.

pages 411-412. # 28, 37, 38, 39

Friday April 24th

Today's topic is independent events.  The formula is another one we did in statistics.  Events are independent if. P(A and B) = P(A) x P(B).  That should be all you need to do this assignment.  Page 409-410 #1,2,5-14

Don't forget there's another formula for independence:  P(A/B) = P(A)

Thursday April 23rd

Finish assignment from yesterday. # 30-56  pages 400,401

Friday, April 17th

Quiz day.  You know how this works:  do problems on paper (show work), take a picture and e-mail to me.

1)  A coin is tossed twice.  Write a probability model (sample space and probabilities)

2)  A jar contains 3 white marbles and 5 red marbles.  You pick one, then put it back and pick another one.

What is the probability that both are red?

What is the probability that the first is red and the second is white?

What is the probability that you get 1 of each color?

3)  Five cards are dealt from a deck of cards.  What is the probability that exactly 3 of the cards are aces?