Hi, I am trying to create a formula question using this formula: 
The initial values would be, for example:
I would also like to make FV, r and n variable so that students would get different questions.
Thank you in advance!
Hi, I am trying to create a formula question using this formula:
The initial values would be, for example:
I would also like to make FV, r and n variable so that students would get different questions.
Thank you in advance!
I'm not sure what level of advice you're seeking here, so I'll start at the beginning and then people can go deeper if you need it.
Have you seen these documents in the Canvas Instructor's Guide?
Note that the examples in the guides use mostly integers, but there is nothing to keep you from randomly generating decimals.
You won't be able to format the equation like a mathematical expression, but you can approximate it in a linear fashion.
PV = FV / (1 + r)^n
You could even use the x^2 button on the toolbar to raise the n up rather than using the ^ symbol.
When you enter the formula in the text of the question, you type
PV = [FV] / ( 1 +[r] )^[n]
Then it will allow you to specify the range of values and the number of decimals for each one.
Dear James Jones,
thank you very much for your answer! The question now generates several variables and I am very happy to have learned something new!
James is spot on with his resources for you. When I was in the classroom, I used to format my questions like this:
Then the symbols in [brackets] are replaced by the random numbers from the formula question. It's not perfect, as we'd all rather have the variable directly in the formula, but it does get the job done.
Hey Mike, thanks for chiming in. I thought about adding something like that, but wasn't sure what level Marija was at. You're correct that you cannot use variable substitutions inside an equation. I think I once tricked Canvas into making it work with MathML, but I would consider that more of an failure to catch it than a feature to rely on.
One note -- PV and FV are present value and future value and are each a single item, not P*V and F*V. The good news is that Canvas allows for multicharacter variable names, so you can use [FV] directly. The examples all show single characters for variable names, so people are often unaware that you can have more. The recently updated Formula Quiz Question Helper Functions PDF does show some multi-letter variable names, but the examples in the main documentation don't.
I don't use Canvas for my finance problems, but if I were to do so, here's how I would get around the lack of mathematical formatting with generated values:
Tommy is going to prison for [n] years for felony tax evasion. He managed to stash some money away before the FBI seized his assets and wants to invest part of that money in an off-shore account that pays a nominal interest rate of [r]%, compounded monthly. How much should he invest before going to prison if he wishes to have $[FV],000 in the account when he gets out of prison?
The solution would be PV = 1000*FV/(1+r/1200)^(12*n)
The $[FV],000 is a hack since Canvas won't let you generate multiples of 1000 with it's random number generator, yet the problem becomes unrealistic if you say Tommy wants to have $235,162 when get gets out of Jail. You do need to make sure FV is a positive integer if you do it this way.
The r/1200 is really r/100/12. The r/100 takes the percentage and converts it to a decimal, and then that divides by 12, which converts it from the annual nominal rate to the monthly periodic rate.
I have to chuckle at myself... When I see PV, I think Pressure & Volume. My science background was leading me away from Present Value and Future Value. I was thinking "well, you can just divide volume out of both sides." haha
Great clarification - Thanks!
My Finite text never uses PV and FV in the same problem, so I had to decode the problem first myself.
Marija Cuculic,
I'm not sure what level of advice you're seeking here, so I'll start at the beginning and then people can go deeper if you need it.
Have you seen these documents in the Canvas Instructor's Guide?
Note that the examples in the guides use mostly integers, but there is nothing to keep you from randomly generating decimals.
You won't be able to format the equation like a mathematical expression, but you can approximate it in a linear fashion.
PV = FV / (1 + r)^n
You could even use the x^2 button on the toolbar to raise the n up rather than using the ^ symbol.
When you enter the formula in the text of the question, you type
PV = [FV] / ( 1 +[r] )^[n]
Then it will allow you to specify the range of values and the number of decimals for each one.