Some interesting puzzles....

While I was surfing through a forum about GRE exams I saw some wonderful puzzles.

From those puzzles,I have posted some here....Solving them involves lateral thinking...

1.There are three houses, and three utilities: gas, electricity and water. Your task is to connect each house to all three utilities. Therefore each house will have three lines and each utility will also have three lines. However, you cannot cross lines. You cannot pass lines through houses or utilities. You cannot share lines. Can you draw the 9 lines required?

2.Three people check into a hotel. They pay £30 to the manager and go to their room. The manager suddenly remembers that the room rate is £25 and gives £5 to the bellboy to return to the people. On the way to the room the bellboy reasons that £5 would be difficult to share among three people so he pockets £2 and gives £1 to each person. Now each person paid £10 and got back £1. So they paid £9 each, totalling £27. The bellboy has £2, totalling £29. Where is the missing £1?

3.Once upon a time, and old lady went to sell her vast quantity of eggs at the local market.

When asked how many she had, she replied:

Son, I can't count past 100 but I know that.

If you divide the number of eggs by 2 there will be one egg left.

If you divide the number of eggs by 3 there will be one egg left.

If you divide the number of eggs by 4 there will be one egg left.

If you divide the number of eggs by 5 there will be one egg left.

If you divide the number of eggs by 6 there will be one egg left.

If you divide the number of eggs by 7 there will be one egg left.

If you divide the number of eggs by 8 there will be one egg left.

If you divide the number of eggs by 9 there will be one egg left.

If you divide the number of eggs by 10 there will be one egg left.

Finally. If you divide the Number of eggs by 11 there will be NO EGGS left!

How many eggs did the old lady have?

Solutions:

Read the solutions only after making a genuine attempt in solving the above puzzles.

1.This puzzle is a classic one which has no solution in 2D. However, if you place the items on a doughnut shape in 3D you can solve it. In the picture below, E is linked to 3 by going over the top and re-entering through the hole in the middle.

2.We have to be careful what we are adding together. Originally, they paid £30, they each received back £1, thus they now have only paid £27. Of this £27, £25 went to the manager for the room and £2 went to the bellboy.(This puzzle was used in a tamil film Rassaiyah for a comedy scene involving vadivel!!!)

3.25,201 eggs.

This puzzle has a few different methods for finding the solution, one of which is:

Find a number X into which all of the numbers from 2 to 10 divide evenly. You can do this by simply using 2*3*4*5*6*7*8*9*10, but you can find a smaller number by finding the prime factors, a subset of which can be used to form any number from 2 to 10. 2*2*2*3*3*5*7 will do. This comes out to be 2520, and is the lowest number into which all the numbers 2-10 divide evenly.

We can add 1 to this number to satisfy the first 9 constraints of the puzzle (the remainder of 2521/2, 2521/3 ... 2521/10 is one), but this does not satisfy the last constraint, divisibility by 11.

Fortunately, we can multiply X (=2520) by any integer and add 1 and we will still satisfy constraints 1-9. So what Y do we multiply X by so that (X*Y) + 1 is divisible by 11. 2520/11 has a remainder of 1. Thus two 2520s divided by eleven would have a remainder of 1+1 = 2, and so forth...so ten 2520s divided by 11 would have a remainder of 10. This number plus one would divide eleven evenly, as well as also satisfy the first 9 constraints - thus 25201 is the answer.

Hope you liked these puzzles...

Puzzles were taken from:http://www.brainbashers.com/