Money is a special case. First the general case. I'm a US native speaker and will use US examples. Decimal fractions are treated as plural. 0.5 Ω is read as "oh point five ohms." 1.8 mi is read as "one point eight miles." 98.6°F is read as "ninety-eight point six degrees Fahrenheit." When reading out currency in dollars, we do not read the value as a decimal fraction. We do not use the word "point." And we have a variety of special phrases used for special situations, ranging from informal to slangy. The straightforward way, which fits all situations, is "X dollars and Y cents." That is, $179.95 is "one hundred seventy-nine dollars and ninety-five cents." Learn this and use it when speaking yourself. Amounts between $1.21 and $1.99 are often read as "a dollar twenty-one" through "a dollar ninety-nine." When talking about finance and the unit is not dollars, but millions or billions of dollars, we use the regular language, using the word "point." "$1.83 million" is read as "one point eight three million dollars."

You can say 1.67 dollars or one dollar and 67 cents. The key thing is that you have more than one. If you had exactly one, it would be one dollar. this could be for example one twenty dollar bill. Or one one dollar bill. For more than one of something you need to use the plural. So, I could have twenty dollars. If I were counting money, I could have $133.67. This might consist of the following: 1 One hundred dollar bill 1 Twenty dollar bill 1 Ten dollar bill 3 One dollar bills 2 Quarters 1 Dime 1 Nickel 2 Pennies Here, the quantity of each bill (or coin) I have determines if I use the singular or plural when listing the bills or coins individually.

One Dollar and 67 cent

A dollar sixty seven. One dollar and sixty seven. A dollar sixty seen cents, one dollar sixty seven cents. If I were to reiterate is would be A/One dollar and sixty seven cents. The last one one is the one I would learn.

1.67 dollars, or a dollar and 67 cents!