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Today, I would like to explore the rate at which one gets around New York City. I travel to work each day via subway, and I have always wondered what my average speed over the distance of my home to my office. According to www.hopstop.com, my work is exactly 2.58 miles from my home, taking the route it recommends, which happens to be the exact route that I take.
It says:
Walk 0.19 miles to the subway stop.
Travel 2.24 miles on the subway.
Walk 0.15 miles to my office.
It takes me around 25 minutes to make the full trip. How fast am I going?
Well this problem will resemble the last ones we did with percentages. We are looking for miles per hour which can also be stated like this:
Miles
———
Hour
How many miles will it be in one hour if 2.58 miles takes 25 minutes?
2.58 X
——– = ——–
25 60
Cross-multiply and we get:
25x = 60(2.58)
Simplify.
25x = 154.8
Divide both sides by 25.
X = 6.192
I travel at a rate of about 6.2 miles per hour to work. That might not seem like much but it is around twice the speed at which the average person walks. It is also a VERY short commute for living in Manhattan. Also, I am utilizing public transportation and not driving myself, thereby helping the environment.
CD
For my first post, I would like to explore percentages, specifically the percentage of a specific period of time in relation to the total amount of time the person is alive. Let me give you an example:
I have been with my girlfriend since March 12, 2005. As of today (12/11/07), that equals 1005 days.
I was born on September 23rd, 1980. As of today, that equals 9941 days.
We need to come up with an equation that allows us to calculate the percentage of days that I have been with my girlfriend out of the total number of days that I have been alive.
The standard equation for finding a percentage is simple:
Part P
——— = ——— (with P equaling the percentage we are looking for.)
Whole 100
Part would equal 1005 days, because it represents a part of my life of which I am looking for the percentage.
Whole would equal 9941 days, because it represents my whole life, so far.
It would look like this:
1005 P
——— = ———
9941 100
If we solve by cross multiplying,
1005 * 100 = 9941 * P
Then simplify,
100500 = 9941 * P
Divide both sides by 9941 to get the variable by itself on one side of the equation:
10.109 = P
I have been with her for exactly 10.109% of my life, (and let me say that is has been an amazing 10.109%!)
You can use this formula to find this type of percentage for just about anything: Percentage of days spent in school, percentage of days spent in your curent job, percentage of days spent in your current house…the possibilities are endless.
For some help figuring out the number of days (in your life, in your relationship, etc) check out this page:
http://www.timeanddate.com/date/duration.html
Tomorrow we will attempt to find the exact day (in the future) I will hit the 20% and 50% mark.
CD
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