Sorry for this very of topic question but I like to know if it is grammatically correct to mix numbers and letters in an English phrase? The reason for the question is the weekly Skritter progress emails. In those it says e.g. "You've studied for nine hours and 41 minutes this week". I constantly miss the hour part and only see the minutes. Sloppy reading i guess but in at least Swedish it is not appropriate to use this mixture, is it the same in English?

Check this out: http://www.grammarbook.com/numbers/numbers.asp

You're right. They should not be mixed in the same sentence (Rules 1 & 2)

Thank you very much for that great site Lechuan. Gave me answer to this and some other of my questions:-) Really need to improve my English as well as my Chinese. I better get that book too.

You may want to check out the amazon reviews before purchasing....

I don't agree with the explanation in that book (having taught English grammar for many years and working as a translator into English).

The English rule I follow - and it depends on the style guide of a particular publisher usually - is to write numbers as words from one to ten, and from 11 up as figures.

But if the text has a block of statistics, I would write 1 to 10, 11, 20 etc. all as figures because it makes more sense to the reader.

That link says:

Correct:
My 10 cats fought with their 2 cats. No! That's the sort of thing my German source texts do, but it looks odd in English.
My ten cats fought with their two cats. OK
Given the budget constraints, if all 30 history students attend the four plays, then the 7 math students will be able to attend only two plays. (Students are represented with figures; plays are represented with words.) Weird and wrong

Incorrect:
I asked for five pencils, not 50. Correct!

That's just according to my rule, of course, but I'm not alone.

There are various style guides, different for British and US English. For British English, for example, the Economist Style Guide is quite popular.

Point taken Zeppa and thanks for the clarification. I find your rules to suit my personal taste in this matter.

You do agree on avoiding to use a mixture of figures and letters such as in this case?

No! I mean, if you want to avoid a mixture, I wouldn't correct it, but myself, I would use the mixture because one figure is under 11 and the other above. Hence I say 'five pencils, not 50', is correct according to the style guides I use, which is exactly the opposite to what the grammar site says.

There's nothing to stop you devising your own rules or saying that this is like a list of statistics because it's clock time. I had a paragraph full of statistics yesterday and I made them all figures. Percentages are given in figures too.

Horribly complex this stuff.

Well, I'm no style guide, but it was certainly mentioned to me at school once or twice not to mix and match. So I probably wouldn't. My feeling is that lechuan/mandarinboy is right on this one - it is a bit sloppy, but I don't think it's a huge deal. (I'm British).

There are no absolute grammatical rules on this sort of thing- it comes down to style. Simple rules taught at school by well-meaning teachers are misleading at best. Even the Chicago Manual of Style gives quite general recommendations, not absolute rules:

"It’s usual to use numerals in lists, in tables, and in any context where an abundance of numbers makes spelling them out awkward."
http://www.chicagomanualofstyle.org/CMS_FAQ/Numbers/Numbers01.html

"CMOS 9.7 calls for consistency “in the immediate context,” which you might call “within eyeshot”—that is, anywhere you think a reader might be distracted by the inconsistency."
http://www.chicagomanualofstyle.org/CMS_FAQ/Numbers/Numbers05.html

http://www.chicagomanualofstyle.org/CMS_FAQ/Numbers/Numbers_questions01.html

My rule of thumb is: over ten, use numbers, less than ten, use letters. But it's just that, a rule of thumb for *me.* I don't immediately subscribe to any hard and fast "rule" that some textbook says, because they all preach different rules anyway...

Thank you all for this valuable information. For a person such as my self where English is not my native language this is very useful. Also strange in a way since I where hammered in school (a long time ago) to strictly follow English grammar rules. Seems those "rules" in many cases are more of guidelines. Actually same in Swedish, there are many rules but also many guidelines. Having fun with this in Chinese as well since there are so many different styles there as well.

Just for fun, here's the Django template that generates that:

You've studied for {% if hours %}{{hours|apnumber}} hour{{hours|pluralize}} and {% endif %}{{minutes|apnumber}} minute{{minutes|pluralize}}{% ifequal days 7 %} this week{% else %} in the past {{days|apnumber}} day{{days|pluralize}}{% endifequal %} ({{start|date:"n/d"}} - {{end|date:"n/d"}}).

I'll remove the first two |apnumber pieces and it'll always use numerals instead of words, at the small cost of not spelling out the small numbers for both when it would be appropriate. As a fun challenge, if anyone wants to try her hand to make it handle all cases more properly, she's welcome to it--I'll add any improvements. Adding extra template variables is doable if necessary.

I agree with zeppa on this one, it's too much trouble to write out something like "twenty thousand six hundred forty-two" just because you wrote out "seven" earlier in the sentence.