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The best way for you to answer this question is through __experimentation__. I'll give you some suggestions about how I'd go about setting up experiments that can help you determine which gum flavor lasts the longest. Firstly, select which gums you want to test - do you want to cover a variety of flavors, such as spearmint, fruit, "bubblegum flavor," etc. or would you like to try a series of different brands that claim to be the same flavor? Next, get at least 5 of your friends together. I suggest using some of your friends as they're likely all about the same age, and they'll probably be more willing to help you out. You can also offer them free chewing gum :). Your experiments will run over a series of days. I'd recommend testing only one gum per day, and runing the test a few hours after anyone has eaten. Have a stopwatch handy, and use a pencil and paper to record your results. Give each person a piece of gum. Start timing after they put it in their mouth and being chewing, then record the amount of time that passed for each person, until they state they can't taste the flavor anymore. Using graph paper or a spreadsheet program you can plot the amount of time for each person versus a given brand of gum. It's unlikely the time will be exactly the same for everyone, but you can get a range of values for each gum, and calculate an average time. You might also consider repeating experiments multiple times - so give your friends the same gum on different days to make certain your results are consistent and repeatable. Of course, once you have your basic answers, there are certainly further questions you can ask. For instance, you might consider, "What is the effect of a person's age on how long a gum flavor asks?" Use the data you collected in your initial experiments as a baseline. If you repeat these experiments with people of different age groups, do you notice any differences in how long they taste particular flavors? You can also consider how particular compounds may affect taste. For instance, is someone's perception of how long a flavor lasts affected by gargling with salty water, or a teaspoon of Tobasco sauce in a glass of water, beforehand? (If you use the Tobasco sauce, be certain to let the people participating in your experiments know beforehand!)