Real-Life Math Challenge
You’re planning a spaghetti dinner for eight people, but you have only $9 to spend.
You have the ingredient list and prices from five grocery stores. Your job is to compare the options, build a shopping plan, and explain your decisions.
Will buying everything at one store save you the most money—or should you split your shopping between stores?
What You Need
For this challenge, your dinner requires:
- 32 ounces of dry spaghetti
- 48 ounces of tomato-based pasta sauce
- 2 ounces of Parmesan cheese
You already have water, salt, and cooking equipment.
Your Grocery Price Guide
Each price buys one whole package. These are published online prices collected for this classroom activity; actual prices vary by location and date.
| Store | Spaghetti | Tomato-Based Pasta Sauce | Grated Parmesan |
|---|---|---|---|
| Walmart | Great Value: 16 oz — $1.24 | Great Value Traditional: 24 oz — $1.97 | Great Value: 8 oz — $3.00 |
| Target | Good & Gather Pot-Size: 16 oz — $0.99 | Good & Gather Traditional: 24 oz — $1.79 | Market Pantry: 8 oz — $3.19 |
| Safeway | Signature SELECT: 16 oz — $2.49 | Signature SELECT Marinara: 25 oz — $2.99 | Signature SELECT: 8 oz — $5.99 |
| ALDI | Reggano: 32 oz — $2.09 | Specially Selected Marinara: 24 oz — $4.39 | Reggano: 8 oz — $3.09 |
| Kroger | Kroger: 16 oz — $1.33 | Prego Three Cheese: 24 oz — $2.79 | Kroger: 8 oz — $3.49 |
Price sources: Walmart’s product listings. Target’s product listings. Safeway’s pasta bundle listing; the spaghetti uses its listed original price. ALDI’s product listings. Kroger’s product listings.
Shopping Rules
- Stay within $9 before tax.
- Buy enough of every ingredient.
- Pay for whole packages—you cannot buy just 2 ounces from an 8-ounce cheese container.
- You may shop at more than one store.
- Use only the prices in the table. Ignore coupons, memberships, and delivery fees.
- Treat all listed products as acceptable for this dinner. Judge value using cost and quantity.
Build Your Shopping Plan
Copy and complete this table in your response.
| Ingredient | Store chosen | Number of packages | Total ounces purchased | Total cost |
|---|---|---|---|---|
| Spaghetti | ||||
| Pasta sauce | ||||
| Parmesan |
Then calculate:
Total spent: $_____
Money remaining: $9 − $_____ = $_____
Purchase cost per person: Total spent ÷ 8 = $_____
Round the cost per person to the nearest cent.
Explain Your Decisions
After your shopping list, write at least five complete sentences answering these questions:
- Why did you choose each store? Use specific prices and quantities.
- Which spaghetti has the lowest cost per ounce? Does that choice also give you the lowest total cost for the amount you need?
- How much would your groceries cost if you bought everything at Target?
- How much does your plan save compared with that Target trip?
- What ingredients would you have left over?
Helpful formula:
Cost per ounce = Package price ÷ Ounces in the package
The Extra-Stop Challenge
Imagine each store you visit after your first store adds $1 in transportation costs.
Recalculate your total. Would you still split your shopping between stores, or would you change your plan? Explain using numbers.
Your goal: Make a shopping decision you can defend with math.
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31 Responses
If we go to Target to get the ingredients than it will only cost 8.75. Even though some other stores have cheaper prices for parmesan, it would still cost more to travel to many other stores than to just stay at one. We will have 25 cents leftover. It cost 1.10 dollars to feed one person.
I decided to shop at Walmart for all my ingredints Cause the ingredients are cheaper than other stores and my total was $7.21 in total cause I only shopped at walmart and my money remaining is $1.79 is my remaining money.
I would pick Walmart because it’s cheaper than the others. the spaghetti cost $1.24 than the pasta sauce cost $ 1.97 than the grated Parmesan is 3.00 so added all up is $6.00 and if I do 9 -6=$3.00 and than I do 3 divided by 8 equal 0.375 rounded to the nearest cent equals 0.40 cents.
I chose target because the price of the ounces made the most sense to me.The spaghetti that has the lowest cost per ounce is Target.That did give me the lowest cost total for the amount I need.If I bought everything at target wich I did the cost is $8.75.MY plan saved compared with that target trip is 0.25.The ingredients I would have left over is graded parmesan because I only needed 2oz but it comes with 8oz so I would have 6oz left over.
If we go to Target to buy the ingredients, the cost will be only $8.75. Although other stores might offer Parmesan cheese at a lower price, it would end up costing us more to travel to several different shops than to simply buy everything at one. We would have 25 cents left over. Feeding one person costs $1.10.
Ingredient Store chosen Number of packages Total ounces purchased Total cost
Spaghetti Target 2 32 1.98$
Pasta sauce Target 2 48 3.58$
Parmesan Walmart 1 8 3.00$
$Total spent: $8.56
Money remaining: $9 − $8.56 = $0.44 Purchase cost per person: Total spent ÷ 8 = $1.07
I chose Target for the spaghetti and pasta sauce because it was cheaper but the Walmart Parmesan was more cheaper so I decide to go to target first then Walmart.If I bought everything at Target it would have been 8.75. My plan compared to the Target trip I would spend 0.19 cents more if i shop everything at Target. I would have 6 ounces left of the Parmesan.
So if I had to make spaghetti for 8 people with only $9 I would first go to Walmart and get 1 Parmesan for $3.00 then i would stay at Walmart and get the tomato sauce for $1.97 and then 1 spaghetti for $1.24 and then i would be left at $2.79 And i spent $6.21. I choose Walmat because most of the stuff there is cheep so I don´t have to buy much. and that is what i would do to make spaghetti with only $9.
So for the Spaghetti I would go to Target because it will be $2.00 for 32 oz and it will be from Good & Gather Pot-Size.For the Tomato-Based Pasta Sauce I would go to Target because it would be $3.58 and the one that’s not from Target will cost more. Then I will get the get the Grated Parmesan from Walmart because it $3.00 for it and the ones that’s not from Walmart cost more and my money left will be $0.48 if I did the math right.
I chose Target for the spaghetti and pasta sauce because it was cheaper but the Walmart Parmesan was more cheaper so I decide to go to target first then Walmart.If I bought everything at Target it would have been 8.75. My plan compared to the Target trip I would spend 0.19 cents more if i shop everything at Target. I would have 6 ounces left of the Parmesan.
The first store I will go to buy my ingredients Is probably target because Good & Gather Pot-Size Is $0.99 and only has 16oz so I still have 8.01 dollars left so Im still In budget but the next store I will go to is Walmart I will go to Walmart because the tomateo base and pasta sause together cost 1.97 dollars and it has 24oz after this i will go too ALDI to buy the cheese the cheese cost 3.09 dollars at the end If I round up all the money at the end It will cost 6.00 and i will be left with 3.00 dollars
I would pick Walmart because it is cheaper than the others. The Spaghetti cost $1.24 than the pasta sauce cost $1.97 than the grated Parmesan cost $6.00 so than if i do 9-6=3 than 3 divided by 8 equals o.375 equals 0.40 cents.
I decided to shop at Walmart for all my ingredints Cause the ingredients are cheaper than other stores and my total was $7.21 in total cause I only shopped at walmart and my money remaining is $1.79 is my remaining money.
if I had decide to go to a store I would pick Walmart because if I was to buy all the ingredients the total cost will be 7.21 and I would only have 1.79$ left because spaghetti would be 1.24$ and the tomato based pasta sauce is $1.97 and the grated parmesan so I would have a dollar and 79cents left
i will go to target because it is cheaper and i will be having left overs.and i will be eating good.and i will have some money left over.money and get more stuff.
I would go to Walmart because the total cost would be 6.21.$ 9-$6.21= 2.79. 8 divided by 2.79 rounded to the nearest cent is 2.87.
I will go to walmart and for my ingredients so i will have 1.78$ or maybe more heh😼
I would go to Walmart because even though they’re expensive, at least they have a lot of the ingredients and have the brand we use. So the Spaghetti would cost $1.24 and the Sauce will cost $1.97 and the Parmesan cheese will cost $3.18, which will add up to $6.39 and then I would have $2.61 leftover.
I would choose Walmart for my ingredients because it’s cheaper than the other stores. The total will be around 7 dollars. And other stores will probably go over the budget.
If I had to buy dinner for 8 people and only had 9 dollars, this is what I would do: I would buy everything at Target. The spaghetti, which I would buy 2 of, would be 1.98, 32 ounces. Then I would buy 2 tomato pasta sauces, which would be 1.79 each, making it 3.58, 48 ounces. Then I would buy the Parmesan, which is 3.19, 8 ounces.
Total spent: $8.75
Money remaining: $9 − $8.75 = $0.25
Purchase cost per person: Total spent ÷ 8 = $1.09
For the spaghetti, I decided to go to Target for it. The number of packages I’ll get is two, and that will result in 32 ounces of it, and in total costing $1.98. I’ll go to the same store, which is Target, for getting tomato-based pasta sauce. I’ll get 2 packages, which is 48 ounces and will in total cost $3.58. For the Parmesan cheese, even tho Walmart’s is the cheapest at 3 dollars, I’ll still go to Target because it will only cost $3.19, since if I went to Walmart, the $1 in transportation costs will make that $4 which is more. So I’ll get the Parmesan cheese from Target, I’ll get one package and that will be 8 ounces purchased, and in total that will be $3.19. In total for every purchase, I will spend $8.75 which is cheap enough to buy with $9.
I would buy from Walmart because its cheaper and it cost 7.94 with tax boi.
I would buy from Walmart because its cheaper and it cost 7.94 with tax boi. hi. hi. hi. i like catboys in miad costumes.
I will go to target and get spagehetti and garlic bread some hamburger meat and meat balls I love meat balls
I would rather buy from Walmart because the total would be less than the budget. Since we need 32 ounces of dry spaghetti I would have to buy 2 cardboard boxes of dry spaghetti and for spaghetti sauce I would need 48 ounces but since each container has 24 onces I would also have to buy 2 contaniers. Now what’s left is parmesan so for parmesan I would need 2 ounces but since it comes with way more I would only have to buy one bag. So the total calculation is 16+16=32 so that would = 1.24+1.24=$2.48. So now we move on to the pasta sauce so 24+24=48 so that would mean 1.97+1.97=$3.94. Then we move to the parmesan cheese the cheese comes with 8 ounces. So if we add all the amounts together we get $6.94 as the total without tax and our budget was $9. So the total we spent was 6.94 without tax and our money leftover is 2.06.
I would pick Walmart because it’s cheaper than the others. the spaghetti cost $1.24 than the pasta sauce cost $1.97 than the Grated Parmesan cost $3.00 than I did 9-6=3 then I do 3 divided by 8 equals 0.375 Which equals up to 40 cents.
I would shop at Target for the spaghetti and pasta sauce and Walmart for the Parmesan. I would buy two packages of spaghetti for $1.98, two jars of sauce for $3.58, and one package of Parmesan for $3.00. Altogether, I would spend $8.56, so I would have $0.44 left. That would be about $1.07 per person. ALDI has the cheapest spaghetti per ounce, but Target is cheaper for the amount of spaghetti I actually need. If I bought everything at Target, it would cost $8.75, so my plan saves $0.19. I would have 6 ounces of Parmesan left over because I only need 2 ounces. However, if I had to pay an extra $1 for going to another store, my total would be $9.56, which is over my budget, so I would just buy everything at Target for $8.75.
If we split our shopping between ALDI (spaghetti for $2.09), Target (sauce for $3.58), and Walmart (Parmesan cheese for $3.00), the cost of the products alone is $8.67. Visiting two additional stores adds $2.00 in transportation costs ($1 for each extra store), bringing our actual total cost to $10.67. Buying everything at a single store (Target) costs $8.75, with no additional travel stops. Therefore, when factoring in transportation, going to just one store—Target—proves much more economical and stays within the $9 budget.
I chose to buy the spaghetti and sauce at Target because I think they have the best prices. But I got the parmesan at Walmart because it is the cheapest I think. And Target has the cheapest spaghetti per ounce maybe. And if you buy two boxes that is a low price. And if you bought everything at Target it would be $8.75 I think.
Before the dissection, I thought it would be less gross than the grasshopper, but cutting open the eye was actually grosser. I had expected to find just veins or a hard ball inside, but instead, there was a lot of fluid mixed with black bits; the outside was incredibly tough, and when I cut it open, it splattered everywhere—that was the grossest part. I learned that you understand things better by doing them than by just watching or reading a whole book about the subject. I realized that while it looks bad and is really gross, you learn more by actually doing the task. I also ran into some difficulties: the outer shell was extremely hard, and the eye splattered everywhere when opened. Plus, there was this gross, fatty substance around the sides that was absolutely disgusting. I’m still wondering what that fatty tissue around the eye is for, why the eye contained fluid instead of blood, and why it didn’t have all the veins a human eye has. I also don’t know the function of that black layer; honestly, the whole thing left me really confused.
Splitting your trip between Target and Walmart saves you the most money. It allows you to leverage Target’s superior pricing on pasta essentials while capturing Walmart’s lower price on dairy.
I will go to target because spaghetti at target will be 1.98 dollars for 32 ounces, And pasta sauce with 48 ounces 3.58 dollars and I add all of that up the total with be 5.56 plus taxes I think it will be 7.38.