SOLVING PROBLEMS USING ORGANIZED LISTS
Another way of figuring outcomes and calculating probability is to use an organized list/table
Use table format and list each possible combination when given a question For the table make a heading for each option Go through each option systematically to start listing possibilities based on the limits set in the question You should be able to see a pattern in each category of your table
SAMPLE QUESTION Sara has 36 cents. If she only has dimes and pennies, how many different combinations can you make?
UNDERSTAND THE PROBLEM Given: Sara has 36 cents; only dimes and pennies Required: How many combinations can there be
MAKE A PLAN I’ll make an organized list of all the possible combinations Since the number of dimes has a bigger effect on the number of combinations, I’ll start by having the number of dimes be zero and count up from there, while changing the penny column to equal 36
CARRY OUT THE PLAN ComboDimesPenniesTotal
SOLUTION I see a pattern in my list, so I’m sure that I’ve found all the combinations. The dimes category starts at 0 and counts by 1s up to 3. 3 is the maximum number of dimes she can have because 4 dimes would make 40 cents, which is more than she has. The penny column drops by 10 for every increase in the number of dimes. It can’t drop any more once there are only 6. Therefore, if Sara has 36 cents in total, and only has dimes and pennies, there are only 4 possible combinations.