Compare two prices

First the same bar, then the smaller number

Two signs next to each other shout. 40 Kč and 35 Kč. The brain takes 35. Before it takes, ask: the same thing, the same amount, the same unit? 35 for 0.5 l and 40 for 1 l is not a win for 35. It is a trap for the eyes.

A shopper is not a miser. It is a person who does not let a sign lie. The balance from Cashier enters only after that: even a better 40 can be outside the want envelope.

Adam takes a bar 18 Kč “small”. Ema 22 Kč “large”. The large has 2×. Adam ate two small ones for 36. Ema ate one for 22. Adam won the sign. Ema won the snack.

In a web shop 199 vs. 179. 179 with no cable. 199 with a cable that would cost 80. Adam takes 179 again. Then he buys a cable. Ema reads the line “what is in the pack”.

Unit, amount, pack

A comparison has three filters. 1) Is it the same thing (not “almost the same” with another brand, if the brand matters to you — then you compare a mood, admit that). 2) The same amount. 3) The same currency. Only then the number.

Price per unit is school, not an Excel olympiad. 50 Kč / 2 pcs = 25 a piece. A head can do that. A table may. The mark is a decision: I take the larger pack, because the unit is lower and I will eat that amount. Otherwise you bought waste.

Balance: a cheaper unit that empties the envelope still hurts. A comparison is not an order to buy. It is a ban on lying with the eyes.

A parent for big purchases. You for pocket money. You do not compare a card “which is cheaper to tap”. A card is a parent’s wrapper.

Ema wants to shorten it to “it will be fine somehow”. Adam asks what the lesson Compare two prices is for, when a table can do a sum. A sum does not count respect, a PIN, a trap or an envelope. The core is: First the same unit and amount, then the smaller number.

Adults pay the rent. The card, the account and the PIN belong to a parent. A child’s email does not belong here. Pocket-money numbers do not belong on the network. If you break these rules in the lesson “Compare two prices”, you know a word, not the course.

Juice A 30 Kč / 1 l. Juice B 18 Kč / 0.5 l. B per litre 36. A is the lower unit. Adam wants B, because 18. Ema shows 36. Adam may want B, because he drinks half a litre and would pour the rest away. Then B is reasonable. The unit serves, it does not order.

A game: 1000 coins for 79 vs. 500 for 49. 500 is dearer per coin. A pack “a bargain” in the name does not enter the head without dividing.

Practice numbers, not a bank statement. Ema has 80 Kč in the want envelope. Adam pushes a step this lesson can name. When Ema uses the core, either it waits for a parent, or it fits the envelope. If not, anger and a hole are left — proof of pressure, not that the lesson is pointless.

Why this right now

You are in the course Money with Martin, level Shopper. You can write numbers in a notebook or a table, but the topic is money and decisions, not Excel formulas. The account, the card and the PIN belong to a parent. A child’s email does not belong here. Do not put pocket-money numbers on the network.

This is not the Sheets with Martin course. A table may help, but the mark of success is a decision, not SUM.

You will know this lesson by one sentence: First the same unit and amount, then the smaller number. When you can say it to a parent or a teacher, you have the core. The rest is practice, not magic.

50% off with no base is another lie of the eyes. First be able to do two signs. Then a half. Then postage “free”.

Four things you will build from the course

The course has four small projects. You do not have to do them all at once. Today you add only what this lesson can do.

Workshop: two signs on paper

Find two prices of the same kind (a shop window, a flyer, a practice number). Do not scan receipts with details.

1. Write both prices, the amount, the unit. If the amount is missing, it is incomparable — ask or leave it.

2. Convert to one unit. Which number is lower now?

3. Ask the envelope: even the lower one you may not buy.

4. One sentence out loud: “A smaller sign is not always smaller spending.”

You count with converting. If you bought the smaller sign with no amount, go back to juice 0.5 vs 1 l. The eyes lied. The head can divide.

Practice: which bar?

Practice numbers. Count in your head.

1. 40 Kč / 1 pc vs. 70 Kč / 2 pcs. Price per piece? When do I take two, when one?

2. 18 Kč / 0.5 l vs. 30 Kč / 1 l. Who won the unit? When do I still take half a litre?

3. The sign BARGAIN by 500 coins for 49 vs. 1000 for 79. What do you do before a purchase?

4. Why may a balance say no even to a better unit?

Now you 💪

Go through three checks. By each one, tick in your head: do I see it, or not?

1. I can ask about the amount, not only about the sign.
2. I can convert to a unit in my head or on paper.
3. A comparison does not order a purchase.

If something is missing, go back to the steps above. It is not a test for marks. It is a safety net, so you go on with certainty, not with a mess.

What to take from this lesson

• The same bar, then the number.
• An amount you will not eat is not a win.
• BARGAIN is divided, not believed.
• The envelope has the last word.
• Names in the examples (Ema, Adam) are made up. Do not put your number, email or photo here.
• Next lesson: When you can do this, go to the next lesson in the same level.

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