A very good question I recently got by email:
I’ve seen where some calculation questions involve a lot of number crunching, like where you have to do five years of iterative values. Is it more efficient to just plug numbers in formulas, where possible, and just move on if time is against you? Also, if time is against you, does writing out formulas and explaining in words how to do calculation give most marks?
This is a very good question. Large, calculation-intensive questions can be very dangerous time-wise, and every exam contains at least one. If a question is, say 10 points, it’s very important to spend no more than 30 minutes on it, even if you run out of time in the calculations.
The safest approach is always to write formulas first. And if it makes sense, even write down the steps you plan to follow to reach a decision (e.g. in the case of an “evaluate” question).
This has 2 major benefits to you:
- You show the grader you know what you need to do (it’s the only way the grader can know)
- By putting down all key formulas, you can take more shortcuts in your calculator operations (e.g. storing values, reusing expressions in the TI-30X calculator, etc.). It is not necessary to write down every single intermediate value as long as you write down the key values and show enough work to show the grader the critical steps you followed to get to the answer. This piece of advice is supported by the fact that MANY model solutions to “show all work” questions omit intermediate values.
A third intangible benefit is that by sketching out the formulas and steps first, it can help focus you on the best way to solve the problem. If you just start frantically punching numbers into your calculator, you’re much more likely to go down the wrong rabbit hole, and this can leave you with nothing to show for your effort if you didn’t write down your formulas first.
In summary, the formulas and verbal steps lay a foundation that will ensure you will at least get the majority of the credit available for the question even if you fumble the calculation or run out of time. The longer the calculation problem, fewer people will get it perfectly right anyway. The model solutions posted by the SOA represent the best answers for each question, and even those often have errors or imperfections.
“Perfect” is not necessary for a 10.
The absolute critical things to avoid are:
- Don’t overspend time on a large calculation problem because every minute you overspend on any one problem is a minute you don’t have to work other (possibly easier) questions.
- Don’t just start typing in your calculator because you may end up going in circles without showing where you meant to go (by writing down formulas).
Go into the exam with an agile mindset and expect adversity. Be willing to “let go” of some problems so that you can maximize your chances of answering other problems accurately. The worst feeling is getting to the end of the morning or afternoon session and not having time to answer an easy question.