Using Unit Price to Find the Best Deal

1. Unit Price

Is buying bigger better? Do you really save money by buying the largest paper towel bundle at the supermarket? Is buying larger quantities at big club membership stores worth it? How can we tell if we are getting the best deal? One way to determine if the 6-roll of paper towels is a better buy than the 12-roll size, is to compare the unit price. The unit price is the cost of a single item or unit of measurement, which we can use to compare goods sold in different weights, sizes and quantities. We can use the unit price of similar or comparable items to determine which one has the lowest unit price and is the cheaper or better buy.

2. Calculating Unit Price

How do you calculate unit price? Unit price is calculated by dividing the price of the item by the quantity or the unit of measurement.

formula to know

Calculation Unit Price

EXAMPLE

A store is selling a 6-pack of soda for $3.42. What is the unit price per soda?

Following the formula, we divide the price of the soda ($3.42) by the number of cans of soda in the pack (6).





The unit price is $0.57 per soda. This means that the store has priced each can of soda within the package at $0.57 or 57 cents per can.

try it

Let’s say we want to purchase a bottle of dishwashing liquid. The store is selling a 90 fluid ounce (fl. oz.) bottle for $6.48.

What is the unit price of the bottle?

The unit price is $0.072 fl. oz. If we round to the nearest cent, the unit price is $0.07 per fl. oz. of dishwashing liquid.

3. Using Unit Price to Find the Best Deal

So, let’s revisit the question asked at the beginning of the section. Is buying the 6-roll of paper towels a better buy than the 12-roll size? Let’s find out by comparing the unit prices of the items. The package with the lower unit price per roll would be the best deal.

EXAMPLE

If the 6-roll package of paper towel costs $5.29 and the 12-roll package of paper towels costs $9.87, which is the better buy?

The 6-roll package costs $5.29. We divide the price by the number of units.



If we round to the nearest cent, we get that the unit price for the 6-roll package is $0.88 per roll.

The 12-roll package costs $9.87. We divide the price by the number of units.



If we round to the nearest cent, we get that the unit price of the 12-roll package is $0.82 per roll.

The unit price of the 12-roll package ($0.82) is less than the unit price for the 6-roll package ($0.88). Based on the unit price, the 12-roll package is the better buy.

EXAMPLE

Two large club membership companies are selling liquid laundry detergent. Company A is selling a 138 fl. oz. bottle for $17.99. Company B is selling a 145 fl. oz. bottle of the same laundry detergent for $18.50. Which is the better buy?

Company A is selling the 138 fl. oz. detergent for $17.24. We divide the price by the measurement.

Unit price for the 138 fl. oz. detergent

If we round to the nearest cent, we get that the unit price for the detergent at Company A is $0.12 per fl. oz.

Company B is selling the 145 fl. oz. detergent for $18.85. We divide the price by the measurement.

Unit price for the 145 fl. oz. detergent

We get that the unit price for the detergent at Company B is $0.13 per fl. oz.

The unit price of the liquid laundry detergent at Company A ($0.12) is less than the unit price for the detergent at Company B ($0.13). Based on the unit price, the bottle of detergent at Company A is the better buy.

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Tom was looking through weekly ads and found two different stores selling boxes with 2 oz. pouches of yogurt.

Store A	Store B
$4.79	$5.94

Store A is selling a 16-pack of the 2 oz. yogurt pouches for $4.79. Store B is selling the same size yogurt pouches in a 24-pack container for $5.94.

Which is the better buy?

Store A is selling the 16-count pouches for $4.79. We divide the price by the quantity.



If we round to the nearest cent, we get that the unit price for each yogurt pouch at Store A is $0.30 per pouch.

Store B is selling the 24-count pouches of yogurt for $5.94. We divide the price by the quantity.



If we round to the nearest cent, we get that the unit price for each yogurt pouch at Store B is $0.25 per pouch.

The unit price of the 2 oz. yogurt pouches at Store B ($0.25) is less than the unit price for the yogurt at Store A ($0.30). Based on the unit price, yogurt at Store B is the better buy.