Determine the Unit Price to find the Best Buy

A few weeks ago I had to make an early-morning run to the grocery store for milk. On my way to the dairy department, I passed through a bargain aisle. A bin full of discounted breakfast cereal caught my eye, so I stopped to investigate. I found that the 22-oz bags were on clearance because they were being discontinued, and I was pleasantly surprised to discover that the expiration date was still several months away.

I added a few bags to my shopping basket, and like any good value-shopper, I headed to the cereal aisle to compare the sale items to the regularly-priced bags. I was surprised to find that the smaller bags of Malt-O-Meal cereals were on sale, and wouldn’t you know, the unit price was actually lower on the smaller bags!

I pulled out my calculator to determine the unit prices:

Small Bag ($2.50 for 15 oz) = $2.50 /15oz
= $0.1667 per ounce

Large Bag ($4.99 for 22 oz) = $4.99/22oz
= $0.2268 per ounce

It was clear that the item on clearance was over priced. However, there was a problem…as you can see from the photo, the shelf was empty and there were no small bags available! This is usually an easy negotiation. Most store managers are happy to match the lowest price. I simply took my $4.99 bags of cereal to the front of the store and asked the manager if he would match the unit price of the smaller bags that were not on clearance.

Spoiler Alert: I was NOT happy with his response!

I showed him the simple math and clearly demonstrated that
if he matched the $0.1667 unit price for the 22oz bag,
the 22oz bag would come to 22oz X $0.1667 = $3.67.

His response was somewhat insulting. He offered to knock the price down to $4.00. I reminded him that the fair price would be $3.67, but he told me, “It is too early to be doing this kind of math. (By “this kind” did he mean 5th grade math?) $4 is the offer.” I told him I would put it back because I was not going to pay $4, and rather than telling me, “Don’t worry; I will have someone else put it back for you”, he added, “Go ahead and put it back. Someone Else Will Buy It”. I responded, “Yeah, someone who can’t do math will buy it”, and he agreed.

By the way, don’t worry about my kids.
I stopped by another Dierbergs Grocery Store later that day and
filled my cart with 15-oz bags that were only
$0.1667 per ounce!

Calculate the Price Increase
to Understand the Effect of Inflation

This photo shows the changing prices for one of my Dad’s favorite cookies from China Town. We can use the simple Percent Change Formula to calculate the percentage increase.

Percent Change = Amount of Change divided by Original Amount

Here are the calculations:

June 2021 to November 2021 = $0.40 increase = $0.40/$1.39 =
28.78% increase over 5 months

November 2021 to January2022 = $0.40 increase = $0.40/$1.79 = 22.35% increase over 2 months

June 2021 to January 2022 = $0.80 increase = $0.80/$1.39 =
57.55% increase over 7 months

Determine the Unit Price to find the Best Buy

• Single Pack of Kraft Singles $4 on Sale / $4.64 Regular Price / 16oz / 24 Slice
• BOX: $12.39 / 48oz / 72 slices

I noticed that Kraft Singles were on sale, but before making a purchase I wanted to compare the various options. There were single packs of 24 slices, double-packs with 32 slices, and boxes with 72 ounces.