Ms. Billett's Math Blog

Percent of Change

2009-10-19T19:44:00.003-07:00

A little blurb about gambling has recently caught my eye in Newsweek. It says that gambling revenues dropped $1.78 billion this year, which is a 2.6% dip.

Your job:
1. Figure out how much the revenues were last year (original)
2. Figure out how much they are this year, after the 2.6% drop. (new)
Hint: Use the formula for percent of change. Remember that the original is 100%.

Traveling In Canada Part 2

2008-10-26T10:41:00.000-07:00

After spending a week with our friends, it was time to head back to the US. Before we left, we had to get some gas for the car. We picked the best price in town, and filled up the tank.

The best price we found was 98.6¢ for one liter. That is in Canadian dollars (or cents to be exact). After we crossed the border and got lost for a while due to inaccurate directions, it was time to fill up the tank again, in the state of New York. The best price we could find was $3.37 for a gallon. That is US dollars.

Your job is to figure out whether gas was cheaper in Canada or in the US?
Here is some additional information to help you:
$1.00 CAN = $ .80 US
1 gallon = 3.8 liters

Traveling in Canada Part 1

2008-10-26T10:22:00.001-07:00

During our stay in Pennsylvania we also took a trip up North to visit some friends of ours in Cobourg, Canada. Cobourg is a small town on the North shore of Lake Ontario. You can click the map on the left to get a better view of its location.

We arrived in Canada at a very exciting time, first because it was the eve of Canadian Thanksgiving, second becasue it was a few days before their election day.

The results of the election are the topic of this problem. According to the official results, the Conservative Party won with about 38% of the votes. From another website I learned that there are 23,401,064 registered voters in Canada, and about 59% of them actually voted in this election.
Your job:

Figure out how many people actually voted for the winning party.
Find out what percentage of registered voters voted for the winning party.
Hint for #2: take your answer from #1, and the total number of registered voters, make it into a fraction, then turn the fraction into a percent

Submitted by Francisco

2008-10-24T13:09:00.000-07:00

My dad's computer credit card problem

My dad got me and my sister a Widows Vista because our old one had a virus. The virus deleted all the memory & documents. It ruined the screen, printer, mouse, and keyboard. We bought Windows Vista, and it had everything except the printer. Vista came at a price of $799.99 without taxes. The printer was $149.99 without the taxes.

Your job is to:
1. find out the taxes (8.25% of the total price) and
2. figure out how much money my dad has to pay per month so he can finish paying in 18 months.

Submitted by Jasmine

2008-10-23T20:43:00.000-07:00

The Shoe Problem

Yesterday I received $100, and decided to go buy shoes. At the the store I saw every pair cost $40 but not just that, each pair was discounted 50%. If each were 50% off, how many pairs can I get? Could I get more than two?

Traveling on the Pennsylvania Turnpike - Part 2

2008-10-16T13:49:00.000-07:00

On our way from Somerset to Reading we were traveling on Pennsylvania's main highway, the the Pennsylvania Turnpike. It is a toll road, and not very scenic, but it gets you to where you want to go pretty fast.

Once you get on the toll road, there is no way to get off without paying, there are toll booths at every exit. This means that the road does not go through any towns, and so you can't just pull over to have a snack or take care of restroom needs. To help travelers, there are so called Service Plazas along the road with tourist information, shops, and restaurants.

We stopped at one of these service centers, and had a cup of coffee at Starbucks. At the counter where you add sugar and cream to your coffee, I found a little questionnaire. You can see the cover on the left, and you can click the picture to see the inside of the questionnaire. It is asking costumers to fill out the questionnaire and mail it in.

Your job is to answer the following question: Which sampling method is Starbucks using for tis study? Explain how you decided on the answer.
Here is a picture of me at the Travel Plaza:

Traveling on the Pennsylvania Turnpike - Part 1

2008-10-16T12:37:00.000-07:00

Mr. Billett and I have been traveling in Pennsylvania this month. One place we visited was a famous house designed by Frank Loyd Wright. The house is called Falling Water, because it was built over a creek and waterfall. The house was spectacular.

Before we visited the house, we were staying with Mr. Billett senior, near the city of Reading in Pennsylvania. To have enough time to visit Falling Water and the neighboring area, we spent a couple nights in the town of Somerset. We also visited the city of Pittsburgh on a rainy day.

Pennsylvania's main highway is the Pennsylvania Turnpike. It is a toll road, and not very scenic. On the way there we took smaller, more interesting roads, but on the way home we decided to save time, and take the Turnpike. The toll on the pike is proportional to the distance you travel on it. Each exit is numbered according to its distance from the Western end of the turnpike. (see picture below, click to enlarge it.)

From Pittsburgh (mile 57) to Somerset (mile 110) we paid $3.00 for the toll. The next day we were traveling from Somerset (mile 110) to Reading (mile 286). Your job: figure out about how much the toll would be for that distance.

Rainfall

2008-09-18T09:53:00.001-07:00

Lately there have been a lot of talk about Hurricanes wrecking the coastal regions of the US. The latest one on the news is Hurricane Ike. One statistic that I heard about this hurricane was that here in Los Angeles we have had 0.16 inches of rainfall from March 2008 to September 2008, while Hurricane Ike produced 15.75 inches of rain in just a few days in Houston, Texas.

Below are the graphs that show the average precipitation for the two cities from The Weather Channel Click on the image to enlarge it and see the numbers clearer.
Your job is to answer the following questions:

About how many years of average Los Angeles precipitation would equal the rainfall produced by Ike in Houston?
About how many months of average Houston precipitation would equal the rainfall produced by Ike?

Remember to explain how you found the answers to the questions.

Rosario's Dilemma

2008-09-18T09:53:00.000-07:00

The following problem was submitted by Rosario.

Today my dad bought a box of chocolates. It contained 48 pieces. If they shared the 48 pieces equally, each of my household members (not including me) would have gotten 9.6 bars. But I want some too. :)

I need your help to figure out exactly how many bars each person should get. And how many people there are in total.

Huntington Park's Population

2008-09-05T14:23:00.000-07:00

I was recently browsing the official website of the City of Huntington Park, home of Gage Middle School, and I stumbled upon some demographic information that got me thinking.
According to the site:

Total population of HP: 61,348
Hispanic population: 58, 636
Registered voters: 13,137

These numbers made me wonder about percentages and languages. Your task is to answer the following questions:

What percentage of the residents of Huntington Park are Hispanic?
What percentage of the residents of Huntington Park are registered to vote?
Do you think the large number of Hispanics living in the city means that the city's website should be bilingual? (see poll on the right)

Email me the answers to the first 2 questions. To answer the third, you can respond to the poll on the right.

HINT: To figure out the percents, start by figuring out the fraction (how many Hispanic out of how many total, and how many registered to vote out of how many total) then turn the fraction into a decimal, then a percent. You can use a calculator if you prefer.

Brandon's Dilemma

2008-06-10T07:35:00.000-07:00

One of my friends and neighbors, Brandon, recently added raised beds to his backyard. He plans to use them to grow vegetables for his family. He built the beds and was getting ready to fill them with soil when he came to us for advice. Here is his dilemma:

He has two raised beds, each measuring 10 feet by 10 feet, and they are 6 inches deep. The soil he wants to fill them with is sold in cubic yards. He asked us to help him figure out how many cubic yards of soil he should get. Can you help out?

Here are a couple of hints for figuring out the answer:

Convert all measurements into yards. How? Here is some information that may help you: 1 yard = 3 feet, 1 foot = 12 inches, 1 yard = 36 inches
Calculate the volume of one bed in cubic yards, then double the answer, since there are two beds.

The next question is, how much will he pay for all that soil if one cubic yard costs #20?

Good luck, and I am looking forward to your emails with answers and explanations. :)

The Oinkster: A Slow Fast Food Restaurant

2008-05-04T09:09:00.000-07:00

During one of those hot hot Spring weekends, we decided to go out and have a hamburger to lunch. We picked a restaurant called "The Oinkster." Their motto is that they are a slow fast food restaurant. I think they mean that they serve traditional fast food type dishes, but they prepare it fresh, and so you need to wait for it a little bit.

We had our burgers, and fries, and salad, and we were just about ready to leave when I noticed a little survey on the table. I took one with me, click the Oinkster logo below to see it.

Your job is to look at the survey and answer these questions:

What type of sampling method is Oinkster using for this survey? Explain/justify your answer.
Describe another sampling method they could have used.
What would be the best way to sample Oinkster customers for this survey?

Sunday Times

2008-04-09T18:45:00.000-07:00

Mr. Billett and I have the Sunday edition of the LA Times delivered to our door. We recently got a bill, and Mr. Billett sat down to figure out whether we are saving money by having the paper delivered, or whether it would be better to walk down to the corner and pick one up in person every Sunday.

According to the bill, we paid $17.20 to have the paper delivered every Sunday between 03/10/08 and 05/05/08. The price of the Sunday Times is $1.25 if you buy it in person.

Your job is to figure out:
1. Which is the better deal: delivery or walking to get the paper?
2. How much would we save over a whole year with the better deal?

Submitted by Jazmin

2008-02-03T16:58:00.000-08:00

The following problem was submitted by one of my students, Jazmin. It is an excellent example of everyday Math.

Curtains

2008-01-21T12:17:00.000-08:00

Ten years after moving into our house, we finally decided to trade the tired looking blinds in the living room and dining room for cozy curtains. First I went downtown to the fashion district, and purchased some lovely material. (see photo) Then, I did a lot of measuring of all the windows, and started sewing the curtains. Mr. Billett volunteered to pick out an order the curtain rods, rings and clips.
As he was looking for curtain rods online, he asked me how wide each panel was, so that he can figure out how many rings to get. The website we ordered from suggested four rings per foot. Unfortunately, I measured the curtains in centimeters, because I grew up in Hungary using the metric system, and feel more comfortable with it. When I told him the width of one panel was 230 cm, he had to do some math to figure out how many rings to order, keeping in mind that we will need two panels for one window. He did it, can you?

NASA Survey

2008-01-05T08:52:00.000-08:00

The National Aeronautics and Space Administration (NASA) recently released the results of a survey conducted among airline pilots. The release of the results was delayed because NASA officials thought the findings would scare airline passengers. Here are some of the numbers as reported by the Associated Press.

The survey showed:

1,266 incidents in which aircraft flew within 500 feet of each other (near miss)
1,312 cases where pilots suddenly dropped or climbed accidentally more than 300 feet in flight
166 reports of pilots landing without clearance (permission) at an airport

What is your interpretation of this data? Do you find it scary? Can you tell the true meaning of these numbers? What additional information would help make sense of the information?

The Real Mac Pro

2007-12-26T19:07:00.000-08:00

On Sunday, December 23, Mr. Billett's 6-year-old G4 stopped working once and for all.

So the next day we went to the Apple store at the Glendale Galleria, and picked up a brand new Mac Pro to replace it. The Apple store was a lot of fun - we tried the iPhone, the new iPod nano, and got expert advice from Josh, a friendly sales associate. Lucky for us, Apple offers an educational discount. The regular price for the Mac Pro is $2499, but with the educators' discount, we paid $2299.

Your job is to figure out about what percentage was our savings. It may seem complicated at first, but proportions, our good old friends, will come to the rescue. Here's how:
Here is another hint to make your job easier: You can round the total price and the sale price to the nearest hundred.

Wedding Bells

2007-12-26T15:25:00.000-08:00

On December 22 Mr. Billett and I attended a party to celebrate our friend Tom and Lisa's marriage. Tom and Lisa live in Switzerland, where she works for the World Health Organization as a nutritionist. We bought them a gift card for $100. Your job is to find out how much this gift is worth in Switzerland, in Swiss Francs. You can use Yahoo Finance to find the exchange rate.

Story Problems

2007-12-19T18:32:00.000-08:00

(click the picture to enlarge)

Mr. Billett found this cartoon by Lynda Barry while he was reading the paper the other day. It makes fun of math word problems by exploring their "back-story", which is the history behind a situation. I thought it was relevant because we have been solving a lot of word problems involving proportions recently. (Click here to download the handouts under homework assignments for 12/17 and 12/12.)

To receive extra credit, you can make up a problem of your own, and come up with questions about the back-story like the girl in the cartoon. If you are working on this at school, you can use Comic Life to create an additional panel for the cartoon and email it to me.

If you choose to comment on this post, select a story problem we worked on in class, and make up some back-stroy questions for it. Have fun!

Christmas Package

2007-12-13T10:49:00.000-08:00

With the holidays fast approaching, I am sending Christmas Packages to my family and friends in Hungary. According to the United States Postal Service Website, the maximum size of a package to Hungary is as follows:

Maximum length: 42 inches

Maximum length and girth combined: 79 inches

I bought a box yesterday that measures 24in x 18in x 10in. It is the perfect size for the last package I need to ship, but is it within the size limits of the Post Office? Can I use this box?

Email me an answer (yes or no) and an explanation to get extra credit points. You may also post a comment.

Hint: the length of the package is the longest side

girth means how big it is around

Pea Soup

2007-12-10T12:21:00.000-08:00

Yesterday I was cooking pea soup for dinner. I found a great recipe on the internet, I had all the ingredients too. The recipe was for 300 grams of peas. (I found it on a Hungarian cooking website, we use the metric system in Hungary, so we measure weight in grams, not pounds.) When I looked at the package of frozen peas I had at home, it said it has 450 grams of peas. I wanted to use the whole bag, so I had to figure out how much of the other ingredients I should use. I did it, can you? Here are the original ingredients, your job is to figure out how much of each I should use, then email me with your answers and an explanation of how you figured them out. If you decide to comment on this post, tell me something about recipes and math, or the metric system. Good luck.

Pea Soup Ingredients
300 grams peas
3 deciliters milk
30 grams butter
1 tablespoon flour
1 teaspoon sugar
1 deciliter cream
1 egg yolk

PS: The soup came out delicious, even though it looks a little funny because it's bright green.

Introduction

2007-12-10T12:12:00.000-08:00

Hi, and welcome to Ms. Billett's math blog. The entries in this blog illustrate how math really is everywhere, and how you can't really get by without knowing your math. Each entry will contain a problem or question. You can send me an email with your answer to get extra credit points. You can also post comments, if they relate to math, you may get extra credit points for those as well. Good luck.