Answer: $178 = One hundred and seventy-eight dollars. $1.78 = One dollar and seventy-eight cents.

My answers are for American English (of course). First, there’s no “seventeen”. We can say “a hundred seventy-eight dollars” for $178.00. We can say “a dollar seventy-eight (cents)” for $1.78. In this context, we can say “one” or “a” with no difference in meaning, although we would usually say “one” if we wanted to emphasize that. Also, note that we can refer to “dollars” as “bucks” in everyday speech. In casual speech, we can say “one seventy-eight” for both prices. If the meaning is not obvious from context, you’ve got bigger fish to fry. Question 2: It’s true that ”the babies' diaper" and" the baby's diaper" are both pronounced the same, however it will be obvious from the context. Also, if there are multiple babies, there will normally be multiple diapers.

Usually, I would say "one-hundred seventy-eight dollars" for the first example and "one seventy-eight" for the second example. We would not say "one seventeen-eight dollars" for either. To distinguish, you can always say "dollars" after the first example. Usually, context will also help determine which amount you mean. For example, if you said "I paid one seventy-eight for this candy bar" I would assume you mean $1.78 and not $178.00. For your second question, they do have the same pronunciation, but the nouns are different. We would say "the babies' DIAPERS" not "the babies' DIAPER" because there is more than one diaper for more than one baby. This distinguishes it from "the baby's DIAPER" where there is only one diaper for one baby. In other examples, sometimes the pronunciation is the same also and you must use context to decide. I hope this helps you!

It all depends in the context and what your buying would tell you the difference when saying 178 verbally.

I think you meant one seventy-eight in your question. As for differentiating between $178 and $1.78 larger context of the conversation will matter. Are you talking about buying clothes or some small snack? If not then hearing one seventeen-eight I would be thinking of a number like 1178 but would be very confused by the statement. We (most Americans) would use something like seventeen-eight if you were talking about a car or something like that -- but then it would mean 17,800 (or perhaps large if you're talking about things that cost millions).