If you are presented with the Amount Error Dialog, Mangia! is having trouble making sense of an amount as you typed it. An amount, or quantity, is a number (or range of numbers) followed by a unit of measurement. In this dialog you are being asked to type them into separate text boxes for the purposed of clarification.
The number can be a simple whole number for example, "1" or "256." It can also have a fraction, so "3 3/4" and "12 5/8" are also acceptable numbers. Furthermore, you can also type a range of numbers, like "3 1/2 to 5."
The unit has to match something in Mangia! ‘s Dictionary. As usual, you can either type it directly into the box labelled Unit: or pick it by clicking on the Dictionary Button.
