27 April 2011

One more coin

There are 101 completely unbiased identical coins. You give your friend 50 and you take 51 of them. Both of you toss all the coins you have. What is the probability that you will land up with more heads than your friend?

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23 April 2011

First Turtle Trot 5K

On April 23, 2011, I ran my first run this year. I have been staying away from races as I try to master the Pose Method of Running. I am afraid, going for speed, I will fall back into old style.

It was the First Turtle Trot 5K at Cumming, GA. The money raised is to go to Tybee Marine Research Center. Melanie was there also in the race.

Posted a 24:18 time. The first half I was disciplined. The second half, I fell back to old ways 🙁


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21 April 2011

Table and coins

You and your friend are sitting across a perfectly round table and have a bunch of identical quarters. You two will alternately place quarters flat on the table such that a quarter will not overhang the boundary of the table nor overlap on another quarter. Whoever runs out of space, loses. You go first. How will you ensure that you win?

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14 April 2011

Breaking a 40 lb rock

You have a stone weighing 40 pounds. You have to break it up into 4 parts such that using those weights in a scale and pan balance you can weigh anything from 1 pound to 40 pounds (integers only) Example: if you broke them as 5,5, 7 and 23, you can get 2 by putting 7 on one side and 2 on another. What are those 4 weights?

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9 April 2011

7 with three 2s

How can you get 7 using only three 2s. You can use plus, minus, multiply, divide, square root, factorial, decimal point, log, “to the power of” and parentheses. As many times as you want. You can also put digits together to form … let’s say 22.