4. What are the odds that a randomly selected number between 1 and 100 will not have a digit 7?
(For instance, 23 does not have a digit 7, but 73 does.)

5. There are 4 slots, each containing any of letters a, m, h, t.

HINT:
What are the odds that letters stored in these slots read the word math?
Remember that each slot may contain any of the 4 letters. For this problem "aaaa" is a possibility.

6. Consider strings of length 9 with elements being a, b or c. How many strings will contain at least 6 bâ??s?

HINT:
This one is probably the most difficult problem on the homework. Try to break up the event of "AT LEAST 6 bâ??s" into smaller mutually exclusive events that are easier to work with. For example, consider first finding the number of ways that a string could contain EXACTLY 6 bâ??s. Then try EXACTLY 7 bâ??s...
Once you found how many ways to have put in the 6 b's, you are not done with the exactly 6 part. You still need to account for the remaining 3 spaces, each of which can be filled with an "a" or "c" (otherwise it wouldn't have 6 b's).

Solution Preview

4. The answer to this question depends on whether 1 and 100 are included in the selected numbers, so I will give you the answers for the difference configurations:
If the number range is from 1 to 99 inclusively, then there are 99 numbers total and 80 do not contain a 7, so 19 do contain a 7. So the odds that a randomly selected number will not ...

... c. What is the probability the employee attends college ... a conference, what is the likelihood three of the four ... Solution contains calculations of Probabilities. ...

... This posting contains solutions to following problems on Discrete probability distribution. ... the type of malfunction, the service call can take 1,2, 3, or 4 ...

... 2) A standard 6-sided die is weighted so that the probabilities of rolling 2,3,4,5, or 6 are equal and the probability of rolling is 1 is twice the ...

Probability Distributions and Expected Value Problems. Please help answer the following problem. ... 9 x=0 f(x) = { (C/x) x=1,2,3,4,5,6 (where C is a constant). ...

... Find the probability. Solve the problem. 1) How many 6-digit numbers can be formed using the digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, if repetitions of digits are ...

... a dice problem and several problems finding probabilities and percentiles from normal probability distributions. ... if he gets a sum of three, he wins ...

...3. no, one of probabilities is negative. ... No, because the probability of this occurring is not small ... on solving various questions on probabilities and statistical ...