Price by weight calculator
What does 1.34 lb cost at 3.99 a pound, and how much tax is inside a price?
Showing for United States
Price
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The price is rounded to the nearest cent.
Legal-for-trade scale rules vary by state.
Per pound
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- Per kilogram
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- Per ounce
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- Per 100 grams
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Each price is converted from the exact figure and rounded once, so converting a rounded price again can differ by a cent.
Tax inside the price
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- Price before tax
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The price before tax is rounded to the cent and the tax is the rest, so the two always add up to the total. Your tax authority's rules decide how tax is rounded on a receipt.
This is arithmetic on the rate you type. It does not tell you what rate applies or whether an item is taxable.
Enter your numbers to see the result.
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- Open Customize, then Connectors.
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ChatGPT
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Using another AI app? Look in its settings for MCP, add the address as a remote server, and choose no sign-in.
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"Use TallyTill: What does 1.34 lb cost at 3.99 a pound, and how much tax is inside a price?"
What you will see
- The calculator opens in the chat with the numbers you gave already filled in. Change any number and the answer updates.
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How this is worked out
The price of a weighed amount is the weight times the price per unit of weight, rounded to the cent. Prices per pound, kilogram, ounce and 100 grams are converted with exact factors: a pound is exactly 0.45359237 kilograms, and an ounce is one sixteenth of a pound. Each converted price is rounded to the cent once, from the exact figure. For a price that includes tax, the price before tax is the total divided by one plus the tax rate, rounded to the cent, and the tax is what is left, so the two always add up to the total.
A worked example
Example numbers only; use your own. 1.34 lb at 3.99 a pound is 1.34 × 3.99 = 5.3466, so 5.35. A price of 3.99 a pound is 3.99 ÷ 0.45359237 = 8.80 a kilogram, 0.25 an ounce and 0.88 per 100 grams. If 5.00 includes 7 percent tax, the price before tax is 5.00 ÷ 1.07 = 4.67 and the tax is 0.33.
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