One Hundred Lockers

June 12, 2013 4 comments

I found this riddle online. It’s a bit math oriented, but still relatively easy for non-math geeks to solve ūüėõ

Lockers in a row are numbered 1 , 2 , 3 , . . . , 100. At first, all the lockers¬†are opened. A person goes and closes every locker.¬†Next, another person walks by and opens every other locker, starting with locker #2.¬†Thus lockers 2 , 4 , 6 , . . . , 98 , 100 are open. Another person walks by and “toggles” every third locker (ie closes a locker if it is open, opens a locker if it is closed), starting with locker #3. Then another person toggles every¬†fourth locker, starting with #4, etc… This process continues until no more lockers can¬†be altered.

Question: At the end of all the toggling, which lockers will be closed?

Categories: Riddles

Start With Why

May 30, 2013 Leave a comment

One thing my dad keeps telling me is to¬†put a question mark. Many times when he does something a certain way or has something set up, he’ll ask me¬†why I think he did it that way. His goal is to get me to exercise my brain more since there is always a logical answer. One question he asked me was if you look underneath any bathroom or kitchen sink, you will notice the shape of the pipes are curved like this:

Intuitively it makes more sense if the pipe just went vertically through (simpler pipe design and minimizes the amount of material required) so why are these pipes curved? Even though knowing the answer to the plumbing question may have little significance, I’ve found the habit of asking why has helped a lot with my everyday life.


The primary reason I ask¬†why is to better understand how people think.¬†Many times I am much more interested in¬†why people behave the way they do than¬†what¬†they do. For example if I told you I was going into the office to get some work done on a Saturday morning, that doesn’t say much about myself as a person unless you know the reason. The reason could be I want to boast about finishing my project before my coworker who I dislike or I didn’t manage my time well the previous week¬†or¬†my boss asked me a favour and I want to improve the company’s welfare. Depending on the reason, you would have a different, but more accurate impression of me. When you take the time to understand the people around you, you will be able to practice compassion and make their lives better, which in turn increases your sense of well-being.

Solving Problems

Asking¬†why helps you solve problems because you get to the root cause of them. My friend recently lamented chewing gum while cutting onions didn’t prevent tears. In short, when you cut an onion, you damage its cells causing chemicals that were initially separate from one another to react and produce¬†propanethiol S-oxide, a gaseous compound. The gas diffuses in the air and irritates your eyes, causing you to tear up in the body’s attempt to remove the compound. Once you understand why cutting onions causes one to tear up, you will see it is ridiculous to think chewing gum will solve that problem. Therefore possible solutions include freezing the onion (slows down the reaction rate) or cutting it underwater since both minimizes the amount of gas released or wearing goggles (not contacts) to prevent the gas from reaching your eyes.

*Btw cutting onions underwater solves the problem for the same reason why bathroom and kitchen pipes are curved in the earlier plumbing question.

Giving Meaning

I believe one should always be aware of the reason why he or she pursues a certain behaviour or goal. It gives your life meaning, a purpose. One of my goals in a personal development workshop I am participating in is to improve my public speaking skills because I value effective communication. Knowing the reason behind the goal motivates me to work towards it because it provides the destination I can envision. It keeps me on the right path so I don’t lose focus or direction. Otherwise my attitude towards the goal would be¬†what’s the point? This applies to more important things such as career choice and relationships too. Life is long and you are going to have to endure through countless things. As a popular Internet saying goes,¬†when you feel like giving up, remember why you held on for so long.

Here is Simon Sinek’s TEDTalk he gave several years ago (where the title of this blog entry comes from):


He explains why some companies are unsuccessful even when they had all the resources one assume would lead to success and how leaders inspire other people to follow their cause. To summarize his talk in one sentence,¬†people don’t buy what you do, they buy why you do it.

Categories: Life, Personal

Vancouver Ultimate League Summer 2013

May 17, 2013 2 comments

Just wanted to say that I’m excited for this summer’s VUL season :). For the first time, I’m playing two nights a week so I’ll be getting plenty of exercise this summer (the past three seasons I played only once a week).

After the first week of games, I’m feeling pretty good about myself physically. In previous seasons, the first few weeks are tough for me since I’m out of shape from the lack of physical activity during the winter and spring and it takes a while for me to regain the same level of conditioning that I’m accustomed to playing at. However last spring, I played ultimate in a hat league so I’m already in shape for the summer.

This is also the first time since I was introduced to ultimate that I’m playing with new people (it’ll probably be the last time too). We played two games and won both of them by one point so that’s a good start to the season. We had good team chemistry even though most of us hadn’t played together before and everyone received the disc several times which was great since I was afraid some of the new players weren’t going to receive the disc at all during the game.

There are two things that I’ll be working on this summer:

1. Watching my language
Yup I’m serious about this. Whenever I make a bad pass or fail to catch the disc, I usually let out an expletive or two. This detracts from the spirit of the game. Last week, our team got only a 6.7/10 for our spirit score. I’m not sure why, but I’ll assume that part of the reason was due to my swearing.

2. Hucking
Throwing is my weakest area. I’ll be playing handler a lot more this summer since one of the teams I’m on has more inexperienced players. This will give me more opportunities to practice hucking the disc (those who have seen me play will realize that I’m not much of a threat to huck the disc when I have it).

I’m hoping to win the keg of beer at the end of summer. I’ve never been close to winning it, but I’m expecting great things this summer >:)

Categories: Personal, Sports

The Only Lottery Advice You’ll Need

April 12, 2013 Leave a comment

Lotto 6-49 is the most popular lottery in Canada (I think). In short, one picks six numbers between 1 to 49 and if all six numbers match the draw, then he or she wins the jackpot.

The estimated jackpot for this Saturday’s draw is 55 million which is why I’m going to go buy a ticket for the very first time. The probability of winning the jackpot is 1 in 14 million and each set of 6 numbers costs $2. Therefore it makes mathematical sense to buy a ticket only if you can take home 28 million¬†after taxes and everything else. Here the math is simple, but boring and it won’t tell you how to pick the numbers.

However the psychology aspect is more interesting and can help maximize your winnings. The only advice that works is¬†to pick numbers that no one else will pick. Let’s say you pick 1-2-3-4-5-6 and the draw is also 1-2-3-4-5-6. Congratulations you just won the jackpot! However how many other people do you think picked the same set of numbers as you did? Probably a lot which means you would have to split the winnings among everyone else. The set of numbers 1-2-3-4-5-6 has the same chance of being drawn as a random set such as 3-14-24-28-39-47 so if the latter set was drawn, chances are you won’t have to share the jackpot with anyone else.

An incident like this happened in the March 19, 2008 draw (you can view previous winnings numbers here). The winning numbers for that draw were 23-40-41-42-44-45 with bonus 43. As it turns out 239 people picked 40-41-42-43-44-45 meaning they matched 5 plus the bonus number which would normally win a prize of at least $100 000. However due to the number of winners, each person took home only $1193.70. Furthermore the people who matched only 5 of the numbers (without the bonus) won $2223.40, nearly double the 5/6+ prize (thanks Tim for the find). Just imagine matching 5/6+ numbers (the odds are over 1 in 2 million) then finding out you have to share the prize with 238 other people.

Also make sure you have at least two numbers above 31 and at least four numbers above 12. Many people pick dates and months (eg birthdays, anniversaries etc…) when choosing their numbers. Furthermore don’t pick sequences like 5-10-15-20-25-30 or even 1-6-11-16-21-26 because some people find these numbers attractive and will also pick them. Other sequences such as 2-3-5-7-11-13 (prime numbers) and 3-5-8-13-21-34 (Fibonacci¬†numbers) are probably chosen a lot too.

Lotto 6-49 has a chart of the frequency of each number drawn. This data is public and even though each draw is an independent event, many people refuse to believe that fact and will choose the six most frequent winning numbers or six least frequent winning numbers or a combination of both. This is also the same reason why you shouldn’t choose the previous set of winnings numbers. There’s bound to be some people who will try that. I recommend you take the time to make sure no more than three of your numbers fall within any of the sets I mentioned above. It may be inconvenient, but that extra five minutes could be the difference between a $1 000 000 prize and a $10 000 prize.

May the odds be ever in your favour.

Categories: Bulletin, Life

On Password Recovery Questions

April 3, 2013 2 comments

Email (and bank) accounts are probably the most important accounts one has. If one’s email is hacked, then all other accounts (eg Facebook, Twitter, WordPress etc…) associated with that email are compromised since all a hacker has to do next is to go to any site then request a link via email to reset the password and he or she will have access to those accounts too.

Password recovery questions provide users a convenient way to access their account in the event they forget their password. All people have to do is to correctly answer the question and they will be prompted to enter a new password. However many security questions used to recover passwords are terrible and provide anyone with a back-door¬†way to hack an account. After all why would a hacker bother guessing the password when it’s easier to guess the answer to the security question? Let’s look at some…

What high-school did you attend?
Anyone browsing through my blog will realize that I’m from Vancouver. A two-minute google search will tell you that there are only twenty high-schools in Vancouver.

What is your favourite pet’s name?
Here is a list of the most popular names for dogs and cats¬†if you need help guessing…

What is the first musical instrument you ever played?
This is one of five options as a password recovery question for my UBC Student account. For one, I’m asian so take a wild guess as to what instrument I first played at a young age…

Where did you meet your spouse?
I don’t like this question for a different reason. Imagine yourself several years from now looking back at this question. Will you remember the exact answer you put? You could have put¬†Starbucks,¬†cafe, Vancouver, British Columbia, Canada etc...

What is your mother’s maiden/middle name?
This also applies to the names of grandparents, fathers, siblings etc…Children are usually given family-related middle names (at least in my experience when I discuss this with friends). That’s not hard to find on Facebook.

What is your favourite sports team?
If you’re from Chicago, the answer is probably Chicago Blackhawks, Chicago Bulls or Chicago White Sox. If not then it might be¬†New York Yankees, LA Lakers, Manchester United etc…

Interestingly enough, the only sites I’ve seen use password recovery questions are email and bank accounts. As such I recommend removing that feature unless mandatory. Also here’s a website for you to check how secure your passwords are.


Categories: Bulletin, Life

What I Learned From Ultimate

March 25, 2013 Leave a comment

It all started in the summer of 2008 when my friends and I casually tossed the frisbee after our organic chem lectures.¬†To make a long story short (after all I did spend a lot of time learning about the wonders of Grignard additions and Claisen condensations), I enjoyed that activity so I signed up with my friend’s ultimate team when he invited me to join the following fall semester. Four years later, ultimate has become my favourite sport and I’ve learned a lot from playing it:


Being able to compete at a high level against other players is a huge confidence booster since I realized that my height isn’t that big of a detriment as I had initially thought. My biggest highlight is when I caught a callahan (ie intercept the disc in the opponent’s endzone) when my check was a 6’0 200+ lbs man. Also I’ve had to mark a 7′ player once during a game which was an interesting experience…What I lack in height I make up in speed and awareness so many times I can beat my check to any spot on the field to receive a pass from a teammate.


As mentioned earlier, I have good field awareness meaning I know where the other thirteen players on the field are and what they are doing. On offence, I have to look for open space then make a cut to that space without getting in my teammates’ way if they are making their own cuts. On defense (especially for zone), I have to keep an eye on the disc, shift my position accordingly to how the cup moves and intercept any passes thrown within ~15 ft of me. This has helped me outside of ultimate too since I’m generally aware of my surroundings. For example when I’m out with friends, I’m usually the one mentioning to the group if we are disrupting other people or causing them any inconveniences. More on that on a future entry…

Put the team first

The team’s interest collectively takes priority over one’s own personal interests. Our team had a game one weekend, but couldn’t field enough healthy people. Many guys were injured (minor though, nothing serious) and I was gimpy too from an injured knee. We didn’t cancel our game in time and therefore were expected to show up so my injured teammates and I still had to come and play ultimate. It was one of the strangest sights since our team was down one player and all three guys were limping around the field :P. Btw our team still ended up winning that game (and by a respectable margin) ūüėÄ

Women are the MVPs of every game

A co-ed game requires three males, three females and one more person of either gender. Due to this, whether games are played or not depends mostly if a team can field enough women since there are much more men than women playing the sport. I have played countless games where my female teammates had to play the entire game without subs or only one sub and they still play just as hard as the guys. This applies to most other teams too. I’ve also noticed that differences in skill levels among males don’t have as large an impact as differences in skill levels among females. Many times the team that wins an ultimate game is the one with the more-skilled women.

Categories: Personal, Sports, UBC

Ice Cream for Three Boys

March 7, 2013 2 comments

I just realized that I haven’t posted a riddle in over a year so here’s another one…Credits to Jeremy for sharing this riddle:

Three boys, Ken, Kevin, and Kyle, are promised ice cream by the self-proclaimed God of the universe, Khanh, but with a challenge attached. Khanh randomly puts a blue or red hat on each of Ken, Kevin and Kyle. Each boy can see the hats of the other two boys, but not his own hat. Their goal is to guess the colour of their own hat, but they have only one chance to guess. Khanh counts down from 3 out loud and on “1”, the boys must either shout out the colour they think their hat is or keep quiet and not say anything. If any of the boys guesses the colour of his hat incorrectly OR none of the boys says anything, none of them gets ice cream. However as long as at least one person guesses his hat’s colour right and no one else guesses it wrong, then they all get ice cream.

Any form of communication as soon as the first hat is put on, until they make their guesses, is completely forbidden by Khanh. If the boys try to communicate, Khanh will find out and the they won’t get ice cream.

Question: Granted the boys have time to discuss a strategy beforehand, what strategy can they come up with to maximize the chances of getting ice cream? With this strategy, what are the odds that they will get ice cream?

Categories: Riddles