BAII Plus calculator question!

Is there anyway I can get the calulator to show me a fraction instead of a decimal when I’m working with the odds section in the Level I material? Sorry in advance for a possibly dumb question.

I don’t think so, but I could be wrong. Simplest way to do it is by writing the decimal in fraction form over one, then multiply the top and bottom by 100 and reduce.

So, .45 (chance of success) as a decimal is also .45/1

Multiply top and bottom by 100 = 45/100, then reduce. Turns into 9/20.

Another example: .25 = . 25/1

Multiply top and bottom by 100 -> 25/100, reduce = 1/4

What if the chance of occururing is something like 12.5%?

Okay, always first try and divide 1 by your decimal. 1/.125 = 8 That means the fraction for .125 is 1/8

1/.25 = 4, that means the fraction for .25 is 1/4

If that doesn’t work do what I said above. With 12.5%, you should see that it’s half of 25% which is 1/4 -> divide by 2 and it’s 1/8

Or, if you can’t see that it’s half of 25%, you can try and get there slowly. If you see a decimal in form: xx.5 just multiply it by two. In this case, multiplying .125 by 2 will get you .25, which you can easily convert into fraction. Once you get the fraction, divide that fraction by 2.

These methods wont work for every decimal, but I think they’ll serve you well for most type of odds/percent problems CFA will ask. I doubt they’ll ask for the odds of a 34.8% chance of success.

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Where were “odds” in the L1 curriculum?

Earlier part of Quantitative Methods

Thank you soo much, you’re amazing!