How do you measure two-thirds?
November 18th, 2009 by SplineGuy
From an article by Mary Ann Bragg which appeared on CapeCodeOnline and was also printed in this month’s College Mathematics Journal:
TRURO — Voters narrowly approved one of four zoning amendments late Tuesday night at the annual town meeting. But town officials were still looking at the exact vote count on that article yesterday.
In a vote of 136 to 70, voters passed a new time limit on how quickly a cottage colony, cabin colony, motel or hotel can be converted to condominiums. The new limit requires that those properties be in operation for three years before being converted to condominiums.
The idea behind the zoning amendment is to slow the pace of condominium development in Truro and preserve more affordable accommodations for tourists, according to citizens proposing the warrant article.
Currently Truro does not allow condominiums complexes to be built outright in its zoning bylaws. Instead, property owners must build a cottage colony, cabins, motel or hotel first and then covert it to condominiums through a special permit.
The exact count of the vote — 136 to 70 —had town officials hitting their calculators yesterday. The zoning measure needed a two-thirds vote to pass. A calculation by town accountant Trudy Brazil indicated that 136 votes are two-thirds of 206 total votes, said Town Clerk Cynthia Slade.
But is it? Is 136 a sufficient number of votes to be considered two-thirds of the total 206 votes? Let’s check:
If you use the fact that
and then proceed to multiply 206 by 0.66 you get 135.96. There were 136 votes in favor which is more than 135.96 so that means it passes, right? If you think so, then you’d be WRONG!!!
The main problem is the rounding. In fact,
or using repeated decimal notation,
. When you round, you are actually creating an error that, in this case, makes a pretty significant difference.
Think of it another way, lets compare 136 / 206 to 2 / 3. First, just do it by decimal approximation:

My calculator cannot exactly represent either of these fractions but its accurate to 12 decimal places and I can clearly see that 136/206 < 2/3 so the vote should not pass.
Do you remember another way you can compare fractions? Find a common denominator and convert each fraction, then compare.


So, here we see that, again,

This second method of checking is even better than the first because there are no approximations involved. We’ve confirmed, absolutely, that 136 votes out of a total of 206 does NOT constitute two-thirds.
Fortunately, a good citizen made an anonymous call in Truro, MA, to clear this up. What perplexes me is that they decided they needed to let the State Attorney General’s office decide on the correct count. The mathematical explanation wasn’t good enough. Can you say quantitative illiteracy?
This week I was given the privilege of leading our campus Environmental Stewardship Bible Study. Currently the study is walking through various sections of the Bible in order to provide a scriptural foundation for concepts in environmental stewardship. It was my good pleasure to lead a study on Psalms. While the actual Bible Study was driven by some excellent discussion, much of the material in the study below I was unable to get to. This outline has been posted in our Blackboard classroom for the Bible study but I also post it here for those folks that have been following my previous postings on creation care.
In several lengthy discussions that I’ve had with friends and colleagues over my new interest in environmental stewardship, inevitably we begin discussing the stereotypes of environmental activists. Being raised in West Texas my whole life, I haven’t really encountered very many individuals that would be classified as environmental activists, but I’ve certainly heard my fair share of disparaging political epithets: hippy, environmentalist wacko, tree hugger, ecoterrorist, econazi, etc.
So, instead of beginning with the love of nature and its beauty as a motivation of environmental stewardship, I think the best place to begin is in Scripture. After all, the love of the outdoors has not come naturally to the “indoorsman” city-boy that I am. If I do end up an environmental activist (yikes, that still scares me) it will be as one who moved from environmental indifference to environmental concern as a result of my faith and not as one who started out concerned about the environment and added my faith to the reasons for that concern.![\begin{array}{rcl} \displaystyle \frac{dy}{dx} & = & f(x,y) \\[2ex] y(x_0) & = & y_0. \end{array} \begin{array}{rcl} \displaystyle \frac{dy}{dx} & = & f(x,y) \\[2ex] y(x_0) & = & y_0. \end{array}](/latexrender/pictures/e2d6721fc2360ffe9c73a4be3b57e8a2.gif)
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At Wayland, there has been an increased emphasis on the need to "go green". I’ll admit to having inherited a very West Texas conservative viewpoint on the environment. I’ll even go so far as to admit not giving it much thought at all and just taking for granted the natural resources that are available to me.
Here’s something I already know: We are called to be stewards of many things as followers of Christ: stewards of our lives, stewards of our talents and gifts, stewards of our families, and stewards of our finances. God is creator and this world was deemed "good" by Him. We should take care of this Earth, a gift that He gave us to live on. The resources of this world are a gift and we are to be stewards of the Earth just as much as of our lives, family, finances and homes.