# Slides 01.16: Unit Price and Comparison Shopping

Lesson 1.16, one day, 13 slides. All prices marked [update from this week's circular].

## Slide 1: Do now
- A 16 oz box of pasta costs $1.29.
- A 12 oz box of a different brand costs $1.49.
- Which is the better buy? Show your thinking.
Notes: Most pick $1.29 because the number is smaller. Ask: smaller because it is a better deal, or because there is less in the box? Here it is both. The next one is harder.

## Slide 2: Now this one
- 24 oz jar of sauce: $2.29
- 45 oz jar of the same sauce: $3.79
- The big one costs more. Is it the better buy?
- You cannot tell by looking.
Image: the two jars side by side with the prices.

## Slide 3: The rule
- Unit price = price divided by quantity
- $2.29 divided by 24 oz = $0.095 per oz
- $3.79 divided by 45 oz = $0.084 per oz
- The 45 oz jar wins per ounce.
- Write the dollar sign on every answer. No dollar sign means you divided the wrong way.

## Slide 4: The store already did the math
- The shelf tag prints the unit price in small letters.
- The sale price is in big letters.
- Guess which one the store wants you to read.
Image: a photo of a real supermarket shelf tag with the unit price circled.

## Slide 5: Units have to match
- 1 pound = 16 ounces
- $4.99 for a 2 lb bag = $4.99 for 32 oz = $0.156 per oz
- Never compare a per-pound price to a per-ounce price. Convert first.

## Slide 6: Store brand vs name brand
- Often made in the same factory with a different label.
- Usually 20 to 40 percent less.
- Thumb up if you think the store brand wins per ounce.
Image: a store-brand and a name-brand box of the same pasta.
Notes: Reveal with the real packages and the math.

## Slide 7: Small vs bulk
- Bulk usually wins per ounce.
- Bulk only wins if you can use it before it spoils and have a place to keep it.
- Thumb up for the big bag.
Image: an 8 oz bag and a 2 lb bag of shredded cheese.

## Slide 8: Sales tax at the register
- In New York, most grocery food is not taxed.
- Foil, paper plates, cups, soap: taxed.
- Candy, soda, prepared hot food: taxed.
- Our county: about 8.625 percent. [Sal: confirm the local rate]
- A $3.49 roll of foil rings up at $3.79.

## Slide 9: Practice
- Part A: six unit prices. Part B: three better buys. Part D: the bulk trap.
- Pairs. Calculators. 12 minutes.
- Convert pounds to ounces before you compare.
- Peer checkers: help, do not tell.

## Slide 10: The bulk trap
- 10 lb of potatoes for $5.99. 3 lb for $2.99.
- This family eats potatoes twice a month, 2 lb each time, and keeps them in a warm cabinet.
- Which bag?
Notes: Take answers. Build the list on the next slide from what they say.

## Slide 11: When cheaper is not better
- It will spoil before you use it.
- There is no room to store it.
- The family will not eat that much.
- A food rule or allergy rules it out.
- You cannot afford the bigger total today, even though it is cheaper per ounce.
Notes: The last one is the hardest and the most real. Say it plainly.

## Slide 12: Exit card
- 3 steps to find a unit price
- 2 reasons the cheaper unit price can be the wrong buy
- 1 item your family buys where you now want to check the shelf tag

## Slide 13: Tomorrow
- You bought it. You got it home. Where does it go?
- Bring back the answer to: what temperature should a refrigerator be?
Image: an open refrigerator, shelves empty.