If I paid $3300 rent for the semester (18 weeks) how much is that monthly? I know there is some formula to convert weekly paycheck to monthly, but I don’t know it.
I suck. 
Depends slightly on which months your semester covered. Using 31-day months you get $811.90 per month.
Well it depends on where exactly the 18 weeks fall in the year, but it works out as about $800 per month.
I got ~$797 using using 30.4375 days per month (the average number of days per month in a typical 4 year period.)
Thanks. I just need an average. It’s for stupid government financial aid forms. The exact dates are 9/16 to 1/20.
Pants, what do you do with the 30.4375 to get the answer? I’m sorry, I went up through college algebra but math doesn’t stay in my head unless I’m currently learning it.
Blob, you don’t suck, but you’re looking for a formula where logic might be more valuable. If you paid $3300 and that was supposed to cover 18 weeks, you might logically figure out that with 7 days in a week, that money covered 126 days. How many months is that? about 4. So you paid $3300 for 4 months’ rent. Seems as if each month must have cost you about $800.
Sometimes just using your natural reasoning will get you someplace. (One problem with most schooling is that kids are taught formulas but they don’t ever get a chance to figure stuff out and to see that the formulas come from logic. Then, the kids grow up and think they suck when they don’t remember the formula.)
Thanks to everyone for your help. I’m just gonna go with $800, and if they want it more exact they can do the math themselves!
CC, I know I don’t really suck, but I swear I’m getting dumber in my old age! Now, what was I doing?
$797.155593 U.S. dollars per month
Google to the rescue!
Cool! I tried it in Wolfram thinking it would be better with a convoluted question, but it didn’t work.
Just don’t go putting ten-thousandths of a cent on your actual response. Eight hundred dollars would be the answer you’d give in science, so that’s what I’d go with.
Situations like this are why the expression “close enough for government work” was invented!
I would have just said, “That’s about 4 months. $3300 / 4 months = $825 a month.”
It’s actually a few days over 4 months, which brings the $/month down a little.
ChileanBob, look up “Dyscalculia.” It’s a real thing and you probably don’t have it–but you might. I only mention this because in my experience it comes as a relief and a boon to find out one has it. (I don’t, but I know someone who does and have read about others.)
(If Dyscalculia is involved, then comments about “common reasoning” won’t help because as soon as Bob has to start doing the calculation 3200/4, his cognitive memory will fail him and he will feel lost.)
Sadly, it wasn’t until college that I was formally taught the concept of “dimensional analysis”; that is, to compare units/dimensions when calculating something and making sure the answer makes sense (in this case, you’re looking for dollars per month, rather than rabbits per spleens or something nonsensical). I think a lot of high school (and even earlier!) math would have made more sense had this concept been made explicit earlier on.
Although the OP has been answered, I’ll go over it for the sake of anyone else who might stumble across this in the hopes it might help them.
In this example, you have 3300 dollars per semester and you want dollars per month.
So take what you know and write it out and use facts that you know (one semester per 18 weeks and approximately 4.3 weeks per month(from Google)) to convert from what you have to what you want.
3300 dollars x 1 semester x 4.3 weeks
semester 18 weeks month
If a unit name appears both on the top and bottom, then they cancel each other out:
3300 dollars x 1 [del]semester[/del] x 4.3 [del]weeks[/del]
[del]semester[/del] 18 [del]weeks[/del] month
You are left with numbers to multiply and divide, and final units of dollars per month:
3300 x 4.3 = 788.33 dollars/month
18
It looks intimidating, but it really isn’t (barring, of course, dyscalculia and other learning issues); it’s simply writing out things that you know in a systematic way to filter it down to the relevant information.