MathCounts Strategy Tips zt

a. GUESS!!! There is no penalty for guessing, so be sure to guess at answers that you don’t know, especially if there are only a few possible answers.

b. Don’t get bogged down. If a problem seems like it will take a long time to complete, just skip it and find problems you can easily answer. Then go back to it if you have time at the end.

c. Look for shorcuts to problems that have an obvious but lengthy solution. For example,
43（17）+ 57（17）can be computed directly, but it is much quicker to use the distributive law:
43（17）+ 57（17）= （43+57）17=100（17）=1700. Almost all MathCounts problems have both a short way and a long way to answer them.

d. Always keep your numbers as small as possible when doing calculations by hand. For example, if
you have to compute
（20*35）/（15*14）
don’t multiply the top and bottom and then try to reduce the resulting fraction like this:
（21*35）/（15*14）=735/210=YUCK!!
instead divide out all the common factors first:
（21*35）/（15*14）=[（3 *7）* （5*7）]/[（3*5）*（2*7）]=7/2

e. Don’t spend a lot of time looking for shortcuts to problems if the obvious solution can be done in under 30 seconds!

f. Almost every MathCounts question has a tiny hint about its answer. They almost always specify the form of the answer only when that form is not an integer. For example, if they do not say that the answer should be written as a mixed number, improper fraction, or decimal, then its almost certain that the answer is an integer (otherwise there could be confusion in grading the problem). Similarly if they tell you to write the number as a mixed number, it is unlikely that the answer will be an integer. If they tell you to write the answer in simplest radical form, or leave your answer in terms of pai（3.1415926）, then it's a good hint that the answer might contain a radical or pai（3.1415926）. This can be a big help in detecting careless errors like giving the correct answer in feet when the problem asks for inches.

g. Have FUN!!!

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