Category: Addition

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Math and Weddings

weddings

In helping a friend plan her wedding, I was recently reminded of how math applies in planning an event. Here are a few ideas to share with your students.

A. Total cost given per-person cost: If the caterer charges $29.50 a guest, and you have 80 guests, how much will food cost? If you increase to 90 guests, how much will your catering cost go up?

B. Total with tip: If your total caterer bill is $2,500, and you add a 20% gratuity off the $2,500, how much would the total with tip be?

C. Here is what you’ve spent on center table decorations: $41.23, $32.12, $20.15, and $50.60. If all that decorates 5 tables, what is the cost per table?

D. The baker charges $356 for a cake that feeds 50. What is the cost per person?

Always remember, math is a useful tool that helps us with real-life tasks!

Solutions: A. $29.50 x 80 =$2,360.00; if increase to 90, total is $29.50 x 90=$2,655.00; difference is $2,655.00-$2,360.00=$295.00.
B. 1.20 x $2,500 = $3,000 (Multiplied by 1.20 to include the 20% tip, as 100% + 20% = 120% = 1.20; could also have found 20% and added that to $2,500).
C. $41.23+$32.12+$20.15+$50.60=$144.10; $144.10/5=$28.82
D. $356/50=$7.12

Algebra 2 eCourseNeed a curriculum that shows students every concept as a useful tool? Check out Kate’s Middle School and High School curriculum, along with elementary supplements that can enrich whatever curriculum you use. Enjoy 30% off most materials through the end of April!

 

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Moving Math

Moving Boxes

My husband and I recently moved into our first home together…and we’ve done a lot of math along the way! Below are a few ways math is used while moving into a new home.

  • Buying the Home – Buying a home requires a lot of paperwork…some of which lists numbers such as your down payment, closing fees you owe, closing fees the seller owes, etc. All those numbers need checked (my husband actually found an error in one draft they had to fix), which requires basic adding and subtracting on a calculator with decimal numbers (and knowing what to add/subtract).
  • Unloading Furniture – Where should we put ______? Determining where furniture goes isn’t always as easy as it sounds. But rather than lifting it and trying it in lots of places (which can be really hard on heavy pieces), measuring the piece and measuring the room (or part of the room) can help figure out where to put it without breaking your back. Addition and subtraction (including of fractions), as well as unit conversion, also come into play. For example, if the window is 45 1/2 inches high and the table comes up 30 3/16 inches, how much space will be between the table and the window? Is it enough for a project that needs to be 5 feet off the floor to sit on?
  • knobInstalling Curtains…and Hanging Pictures – Buying a new home, we had a lot of things we needed to install, from curtains to towel racks to cabinet doorknobs. And then there’s hanging pictures. Measuring helps you know where to drill the hole for the screw/put the nail so it all ends up at the right height. Not only does measuring and basic arithmetic help out here, but so do problem-solving skills. When my husband installed the kitchen drawer handles, he had to think through how to get them centered. After all, neither screw needed to be in the center of the cabinet—the center of the handle needed to be there, but the screws were on the sides of the handle. He had to think through that if he measured the length of the handle and divided it in 2, he’d find the distance from the center of the cabinet on either side he should put the screws in order to have the handle centered.
  • Buying Furniture – What size rug do we need to buy? Will that loveseat fit? If we put the loveseat there, will the recliner still have room to recline back? All of this requires measuring, addition, and subtraction (including sometimes of fractions). When will my furniture arrive if shipping takes 2 weeks? That again requires addition!
  • Budgeting – How much are we spending? How much do we have left to spend? Again, addition and subtraction (with decimal numbers this time) in action!

Math is far from a mere textbook exercise—it helps us complete tasks. Those are only a few tasks math helped my husband and I complete lately.

As you teach math, be sure to let your child use math outside of a textbook too. Doing a home improvement project? Let them help you figure out the cost, make measurements, etc. (If you don’t have a project, you could make a hypothetical one to work on—that could be as simple as seeing if a certain piece of furniture would fit in another room, or how many gallons of paint would be needed to repaint a room (and how much it would cost at $24.99 a gallon).) Remind them that God gave us work to do here on earth, and math is a tool to help us in that work. And it’s a tool we can use while praising the Creator and working to His glory.

Looking for Good Math Materials? Revealing Arithmetic helps you transform the younger grades (plus we sell a complete elementary program), Principles of Mathematics is a complete program (with an optional ecourse) for junior high, we just released an ecourse to go alongside Jacob’s algebra, and we’re getting into the final stages of Algebra 2 (watch for it in early 2021, Lord willing).

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Math Blog: Wedding Math

wedding

Since I’ve been working on planning my wedding, I thought it might be fun to share a glimpse at how math applies in event planning. It truly is a tool we can use in various situations God places us in!

  • Total Guest Count – One interesting aspect of event planning is figuring out how many people are coming…which involves addition in adding up all the friends and families being invited.
  • Budgets – Trying to plan an event on a budget involves adding up all the expenses and subtracting that from the total you have to spend to see how much you have left to spend (or how much over budget you’ve gone…which could be represented with negative numbers). For example, if you’ve spent $25 + $500 + $120, then you’ve spent a total of $645. If your budget is $1,000, you have $1,000 – $645, or $355 left to spend.
  • Total Cost of Items – Addition and multiplication are used extensively in figuring out how much you’re really spending on a specific aspect of the wedding. Take table centerpieces for example. Suppose your centerpiece consists of a $2 vase, a $1 candle, and a $1 a flower . It costs $2 + $1 + 1 = $4. If you have 25 tables to put centerpieces on, it will cost a total of $4 x 25, or $100. If you pay 5% (notice the percent!) sales tax on all of that, then the total cost will be $100 x 1.05 = $105.

As you teach math this week, remember to show your students why they’re learning the concepts they’re learning. Math is about much more than passing a test or solving meaningless problems—we want students to understand how to use this tool in their own life so they’ll be equipped for the various tasks God’s given them…and to do so while praising the great Creator whose faithfulness in holding all things together makes math possible in the first place.

Reminder: If you need ideas or help making math come alive, check out our math resources and curriculum.

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Math Tax Worksheet for Students

Math & Taxes

Math & TaxesWith Federal income taxes nearly due, I thought it might be fun to put together a worksheet you can use with students to let them apply math to filing taxes.

Download Math Tax Worksheet

The worksheet is an extremely simplified version of the 1040, with instructions and pretend numbers for students to use. To use it, students need to know multi-digit addition and subtraction, along with rounding (although you could round the numbers for them if needed).

Please let me know if you find the worksheet helpful. A few of you have suggested that I send out ready-to-go worksheets, so I thought I would give it a try.

Remember, one of the goals in teaching math is to equip students to use math in their own lives to complete various tasks. God created man to work, and math is a tool that can help us in that. We can use math because He gave us the ability; thus we, unlike animals, can even file income taxes. And since income taxes are due each year, it’s an example of how math helps us with real-life tasks.

Math Curriculum & Facebook Q&A

We’ve got math curriculum for elementary to algebra and geometry to help you teach math in a way that connects it with God’s creation and real-life tasks.

Have questions about any of it? Let me know–I’d love to answer them. I’m planning to do a Facebook Live Q&A sometime this week (follow our Facebook page for exact timing and to watch the recording afterwards) and will be addressing lots of common questions there too. Hope you can join in!

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Super Bowl, Super Football Math

Football Math

Football MathHere are a few examples of how you can use the Super Bowl to show your students that math really does apply outside of a textbook.

We learn math, not just to pass a test, but to be equipped to use it to help us in tasks God’s given us here on earth (and to behold His glory and faithfulness in holding all things together—see God and Math?).

Believe it or not, the Super Bowl was replete with examples of math in action.

  • The Super Bowl Name – Notice the Roman numeral in Super Bowl LII. The Super Bowl name (along with the first quarter, second quarter, first down, second down, etc.) is an example of ordinal numbers.
  • The Team Jerseys – Perhaps the most obvious numbers on the field are those on the team jerseys. There’s an example of how we can use numbers like names—in this case, to identify different players.
  • The Field – Yep, there are numbers on the field itself (50-yard line, etc.), and distance is constantly measured throughout the game. How far of a field goal needs kicked? How much distance left to go to get to the next first down? In a more background way, laying out the football field itself required measurements. And how much grass is needed? Or paint? Again, measuring (think geometry) in action!
  • Confetti (and Other Costs and Profits) – So how much confetti was needed to fire off at the end of the game? And how much would it cost? How much did everything at the Super Bowl cost altogether? How much was brought in through ticket sales? Math can help us answer these behind-the-scenes questions.
  • The Ads – A lot of math goes on behind the scenes when it comes to ads. Below are a few examples.
    • How much money did NBC receive in advertising? If you knew the price of the ads sold, that could be calculated using addition. (In 2017, one source said it was around 385 million.)
    • When deciding if they should buy an ad, companies use math to help them compare different options. One useful measurement often used to compare options and develop an overall advertising plan is Gross Rating Points (GRPs), which is found by multiplying two different measurements together.[1] One can also look at how much the ad costs per thousand people it reaches, which is found by dividing the cost of the ad by the total people reached (in thousands).[2]
    • How much does an ad cost altogether? That would take adding up the cost of making the ad, the actual cost of buying the ad space, etc.
    • Is the ad a good ad to run? There’s no perfect way to tell this, but there are a lot of ways to try…and math can help. For example, one could test the ad before paying millions to air it in the Super Bowl. One testing method called the MSW* ARS shows ads (inside programs) to a sample group of people. Ads are given a score based on subtracting the percent that was for the target brand after the ad with the percent that was for the target brand before the ad (in other words, seeing the difference the ad made).[3]
    • Was the ad effective? Again, there’s no perfect way to measure this, but there are a lot of ways to try. Marketers use numerous formulas when evaluating sales and advertising to try to make sure that their advertising is really making a difference in sales.
  • The Graphics – Numerous graphics were introduced throughout the game. While we don’t often think of math and graphic design in the same sentence, graphic design often does use math. Not only does the computer program(s) used in designing use a lot of math behind the scenes, but graphic designers often use math to help position items, scale them, determine proportions, etc. Oh, and colors are specified using—you guessed it—numbers.
  • Statistics – What was the average cost of a 30-second Super Bowl ad? What is the football player’s percent complete? How many yards has the quarterback thrown so far (this would require adding)? And a host of other stats that use numbers (and addition to find those numbers)!
  • The Special Effects – Think of all the work that went in behind the scenes into coordinating various special effects. Math likely had a part in a lot of it: the angles of the lights, the levels of the various microphones (yes, math helps us measure audio levels too!), etc.

A lot goes in to an event like the Super Bowl—including a lot of math. The list above is by no means exhaustive, but hopefully it will get you (and your students) thinking.

Math’s much more than a textbook exercise—it’s a real-life tool we can use while praising the Creator.

Reminder: We’ve got a lot of math resources (and even curriculum) to help you teach math from this perspective.

[1] J. Craig Andrews and Terence A. Shimp, Advertising, Promotion, and Other Aspects of Integrated Marketing Communications, 10th ed. (Boston, MA: Cengage Learning, 2018), p. 348.[2] Ibid., p. 356.

[3] Ibid., p. 386-388.

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Math and the Presidential Primaries

Math and the Presidential PrimariesOne of the things I stress a lot in my math resources is that math isn’t confined to a textbook. As I’ve been following the presidential elections this year, it occurred to me that it provides a great opportunity to show students math in action. Math is used quite a bit behind the scenes in determining each party’s candidate. Consider these applications:

  • Probably the most obvious math concept the elections show in action is percents. What percent of the vote went for each candidate? What percent of a specific area went to each candidate? What percent of the total delegates to a convention does each candidate have pledged to them? How many votes would a candidate have to receive in order to earn a specific percent if 40% of a specific population end up voting?
  • More percents and other math concepts are used in determining how many delegates are actually assigned to each candidate after an election. This article by the Washington Times gives an overview.
  • Addition (along with more percents, as well as formulas) are used behind the scenes in deciding how many delegates each state gets to send to the national conventions in the first place. See The Green Papers: Republican Detailed Delegate Allocation – 2016 for more details about the republican side; and The Green Papers: Democratic Detailed Delegate Allocation – 2016 for the democrat side.
  • Statistics show up extensively throughout the election process. Polls are based on surveying a random sample of the population and trying to determine the views of the whole off of it. It’s a great time to look at how statistics work (and how easily they can be twisted). See Chapter 11 in Principles of Mathematics for an overview and example.

As you follow the elections, consider looking into your particular state’s primary or caucus system and examining the math behind it. Point out the use of percents, addition, etc. Look at the statistics behind a couple of presidential polls and at what they truly tell us.

Then sit back and remember that math only proves useful because this universe is consistent, and because God gave man the ability to subdue the earth. We’re made uniquely in God’s image, created to worship Him. Remind your students that math is far from meaningless bookwork—it’s a real-life tool that helps us in the tasks God has given us to do.