Puzzle 112 - Solution

-

Solution : 0 or 1000 

Let us look at the possible combinations. 

FFT
FTF
TFF 

If only Harry is right, David owns at least one book. But if he owns more than 1000 books, Harry is right. Which means FFT is not a possible solution.

If David owns more than 1000 books, if Thomas is right, then he certainly has at least one book, which means if Thomas is right, Harry should also be right. Which means TFF is not a possible solution.

If David has no books at all, then Thomas is wrong. And Harry is also wrong. But Richard is right because fewer than 1000 can also be zero. 

The other solution is David has exactly 1000 books. If he has 1000 books, Thomas is wrong, Richard is also wrong, but Harry is right - as David has at least one book.

 

 

Comments

Post a Comment

Popular posts from this blog

Puzzle 9 : The 4 coins problem

-
Image
 Solution to puzzle 8: Maria is not counting Sundays. So she is not counting 1/7th of days of her age.  That is to say she is only counting 6/7th of her age. 6/7th of her age = 30 Her actual age = 30 X 7/6 = 210/6 = 35 years.  Puzzle 9 : The 4 coins problem  You’re creating a new coin system for your country. You must use only four coin values and you must be able to create the values 1 through 10 using one coin at a minimum and two coins maximum.    What 4 coins do you choose, and can you think of a second set of 4 coins that achieves the same goal?
Read more

Puzzle 13 - Alibaba's cave

-
Solution to puzzle 12: I am using brute force algorithm here. Let us start from the divisibility of 5. If two cards remain after dealing them for 5, the largest value less than 52 will be 47 If there are 47 cards and they are dealt to 3 people, 2 cards are left If they are dealt to 4 people 47 - 44 = 3 cards are left So 47 is the correct answer. Puzzle 13 : Alibaba's cave This puzzle is from mrbartonmaths Ali Baba found a cave full of gold and diamonds. A bag full of gold weighs 200 kilograms, a bag full of diamonds weighs 40 kilograms. Ali Baba can carry only 100 kilograms at a time. A kilogram of gold costs $20, and a kilogram of diamonds costs $60. What is the greatest amount of money Ali Baba can earn for the gold and diamonds he can carry out at once (in one attempt in one bag)?
Read more

Puzzle 127 - Balanced

-
Image
A scale is balanced. On one side of the scale, there are 3 1 ⁄ 2 bags of rice and on the other side there are 1 3 ⁄ 4 bags of rice and 1 ⁄ 4 kilo weight. What is the weight of one bag of rice? This puzzle is borrowed from the book "Brain teasers" by Ian Livingstone and Jamie Thomson Show answer Let the weight of 1 bag of rice be b. So 3 1 ⁄ 2 b = 1 3 ⁄ 4 b + 1 ⁄ 4 Transferring  1 3 ⁄ 4 b to LHS we get 1 3 ⁄ 4 b =   1 ⁄ 4   b =  1 ⁄ 4  /  1 3 ⁄ 4 =    1 ⁄ 7 kg
Read more