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Q71. Consider this little bit of logic that describes a tourist's thinking process (taken from the title of a 1970s movie): “if it’s Tuesday, this must be Belgium. Otherwise, I have no idea where we are.” Sketch a flowchart that represents this flow of thought.

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This was a good start to modeling.

Q72. Sketch a flowchart that represents this bit of logic: “if you are a woman then if you are over 40 you should have this test no matter what but if either parent had diabetes women should have the test no matter what. Men only need to take the test if they are overweight.”

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This medical advice protocol has two top level parts: one for women and one for men.

For women, it says those over 40 should have the test. And it says no matter what your age, if either parent had diabetes you should have the test.

For men, it says only take the test if you are overweight.

We might be tempted to distraction by phrases like "no matter what" and "only" but a little bit of parsing and rephrasing helps to clarify.

COMMENTS

1. If you have crossing lines in your flow chart something is wrong.
2. You can have more than one action box for a single action — here "take the test" — in order to keep the chart well ordered.
3. Remember, single entry and single exit for each logical subunit.

You can find this solution above.

Q73. Sketch a flowchart that represents this bit of logic: “if cell E$3 is greater than cell G$12 then value is G$12; otherwise, value is G$12-E$3.”

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Q77. Draw a flow charts that represents "Do A until B" and "While B do A. Then do C".

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Q84. If the weather is nice, plant a garden. Otherwise paint the office. For the garden, make a decision between flowers and vegetables. If you go for vegetables, buy compost, seeds, and stakes; till the soil, and hook up the irrigation. If it's flowers this year, go to the garden store and if they have 4 inch plants buy enough for the plot and plant them. If they don't then get flats of smaller plants and bring them home and let them get acclimated for a week and then plant them next week. To till the soil, if the ox is healthy, do it with the animal plow, otherwise get out the rototiller.

Q86. Sort clients into four categories promising, troubling, recalcitrant, hopeless on the basis of two tests which can be passed or failed.

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This is an example of a classic use of flow chart logic to describe a sorting process. Basically we are using two tests to create a 2x2 taxonomy (classification system). It might look like this

Diagnosis	Test 1	Test 2
Promising	Pass	Pass
Troubling	Pass	Fail
Recalcitrant	Fail	Pass
Hopeless	Fail	Fail

Our logic is then

If pass test 1, then if pass test test then "promising" otherwise "troubling." On the other hand, if fail test 1 then if pass test 2 then "recalcitrant" otherwise "hopeless."

Q88. Convert the following statement to “pseudo-Excel” formulas (follow the example to see what we mean by that).
Example. "If it is Tuesday, this must be Belgium, otherwise it is France" would become something like

If the calculated payment (CALC_PMT) is less than the alternative monthly minimum payment (ALT_MIN_PMT) then the payment is the alternative monthly payment otherwise it is the calculated payment.

Q89. Convert the following statement to “pseudo-Excel” formulas (follow the example to see what we mean by that).
Example. "If it is Tuesday, this must be Belgium, otherwise it is France" would become something like

If the current balance (BAL) is less than the calculated payment then pay the balance off, otherwise, pay the calculated payment.

Q90. Convert the following statement to “pseudo-Excel” formulas (follow the example to see what we mean by that).
Example. "If it is Tuesday, this must be Belgium, otherwise it is France" would become something like

If the calculated payment is less than the alternative minimum monthly payment then pay the alternative monthly minimum unless it is more than the remaining balance in which case just pay the balance off. Otherwise pay the calculated payment.