This is actually REALLY ambiguous. The difference between different interpretations is also a little bit more dramatic around this time of the year (February), even during a leap year because it's more than just off by one.

My assumption is that "a month from now" means "this same date next month" -- from today, March 20th.

So does "a month and ten days from now" mean a month from the day that is ten days from now? Or ten days from this day next month?

From today (February 20th), a month from the day that is ten days from now is April 1st because ten days from now is March 1st.

However, from today, ten days from a month from now is March 30th because a month from now is March 20th.

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    This is fundamentally and inescapably ambiguous. It is just possible that context may give you the answer, but I doubt it. If the difference is important, you need to go back to the source and ask. – Colin Fine Feb 21 '16 at 0:31
  • I can't believe anyone would really add the ten days first and then increment the month. And if that was what the speaker intended then they would have stated it differently. Take whatever "a month from now" means and add an additional 10 days. – Jim Feb 21 '16 at 3:08
  • @Jim Aside from referencing the actual day and month, what is an example of how to state it if one intends to add ten days first and then increment the month? This phrase is something I had said intending to refer to April 1st, and then realized the possible misinterpretation. – mjohnsonengr Feb 21 '16 at 3:47
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    Well, you could say 10 days from now plus a month. I don't like this as well, but "a month from 10 days from now" would also work. – Jim Feb 21 '16 at 5:41

As you so rightly point out, this could be ambiguous.

The most natural thing to do would be to take them in the order specified. So first go a month from today, and then go 10 days. This goes to March 30th.

As a general presumption, take the operations in the order specified.

What is a month and 10 days from May 31st? A month from May 31st is June 30th, and the extra 10 days brings us to July 10th.

Whoever wrote this expression should have been more precise, and expressly stated how to deal with months of differing length. If he did not, you can only do your best.

A somewhat similar problem is, what is one year after February 23rd 2015? It is February 23rd 2016. However what is one year after February 24th 2015? It is February 25th 2015. This is because the extra day in a Leap Year is counted as falling on February 24th.

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