"I was just guessing at numbers and figures Pulling your puzzles apart" [Coldplay]
Sunday, May 12, 2024
Sunday, July 10, 2022
Monday, October 11, 2021
Thursday, September 23, 2021
Saturday, June 12, 2021
Sunday, January 24, 2021
Sum of Two Squares
You are going to be randomly assigned a number between 1 and 100 in a party game. For an activity, participants with a number card that is a total of two squares are called. (There are 100 participants)
What is the probability that you will be one of the participants?
Thursday, December 17, 2020
12 Days of Christmas
If we choose three gifts randomly, what is the probability that they are all birds of the same kind?
Monday, October 26, 2020
Parallel Parking
Every weekend, I drive into town for contactless curbside pickup at a local restaurant. Across the street from the restaurant are six parking spots, lined up in a row.
While I can parallel park, it’s definitely not my preference. No parallel parking is required when the rearmost of the six spots is available or when there are two consecutive open spots. If there is a random arrangement of cars currently occupying four of the six spots, what’s the probability that I will have to parallel park?
Source:The Riddler
Three Die Together
Wednesday, July 8, 2020
Sunday, December 29, 2019
Problem 131: Quarter final combinations
Friday, February 1, 2019
Problem 86: Bertrand's Box
Monday, January 28, 2019
Rich Tasks 40: Probability and Science
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https://alportsyndrome.org/alport-syndrome/alport-syndrome-genetics/ |
Sunday, January 20, 2019
Thursday, June 7, 2018
Problem 52: Iceland's World Cup Adventure
Thursday, May 31, 2018
Problem 49: Mr. Oswald's phone
Sunday, May 13, 2018
Problem 46: Feet and Tails
Mrs. Eleanor Abernathy has 7 female cats. This May all her cats gave birth to new kittens. Some of the cats had 3 babies, some had 4 and the remaining ones had 5 baby cats.
The number of cats that gave birth to 5 babies is 1 less than the number of cats that have quadruplets or triplets.
Mrs. Abernathy is interested in counting and she counts 150 legs in her house.
Can you find the number of cats who has quints(5 babies)?
Saturday, May 5, 2018
Problem 43: Alien Encounter
Here is the question:
Sometimes a tree diagram from probability unit is helpful.
So let's try a solution using tree diagrams.
Assume that Alfy tells the truth. Therefore he must be a Veracitor. What he tells about Betty is also true. So Betty is Gibberish. Betty says Alfy and Gemma are same species but she is lying. Therefore Gemma must be Gibberish. This coincides with Gemma saying Betty is Veracitor, which she is not. So Gemma is a liar and it matches with what we found from Alfy and Betty's answers. So our answer is Alfy: Veracitor; Betty and Gemma: Gibberish.
It is better to see the other option where Alfy is dishonest. This time we see that, if he is a liar, then Betty must be a Veracitor. If Betty is Veracitor, then Gemma must be Gibberish since Betty is honest in this option. However being a Gibberish, Gemma must be a liar. However, Gemma says Betty to be a Veracitor which is true. This truth creates a contradiction. Therefore this option is not reasonable at all and Alfy must be telling the truth. So the answer is the previous one.