Logical operators in a flowchart decision

Name:

Date:

Class:

Quick Questions

Shade in the A or B circle for each question.

1. A flowchart must check that a student has a ticket AND has paid. Which design works?

A One diamond: has_ticket = Yes AND paid = Yes

B One diamond: has_ticket = Yes OR paid = Yes

2. Which flowchart gives the same result as one diamond with: score >= 50 AND attendance >= 80?

A Two diamonds side by side, where either one can lead to the pass outcome

B Two diamonds in a row, where the Yes path of the first leads into the second

3. True or false: A single decision diamond can contain a combined condition like temp > 30 OR is_sunny = Yes.

A False

B True

4. A diamond uses OR: is_member = Yes OR has_coupon = Yes. When does the flow take the Yes path?

A When at least one part is true

B Only when both parts are true

5. How can you draw OR using two simple diamonds instead of one?

A Both diamonds have a Yes path that joins the same outcome

B The Yes path of the first diamond leads into the second diamond

Match the Pairs

Draw a line connecting each item on the left to its match on the right.

Left column		Right column
1age >= 13 AND has_permission = Yes		AOR was used when both conditions must be true. It should be AND, because OR lets someone through with only one part true.
2is_weekend = Yes OR is_holiday = Yes		BOne diamond that sends the flow down Yes when at least one part is true
3Two diamonds in a row, where both answers must be Yes to reach the action, can be replaced by one AND diamond		COne diamond that sends the flow down Yes only when both parts are true
4NOT reverses a question so the Yes path is taken when the original answer would have been No		Dscore >= 50 AND attendance >= 80
5Diamond: age >= 13 OR has_permission = Yes (meant to need both)		EAND was used when only one condition needs to be true. It should be OR, because AND needs both to be true at once.
6Diamond: is_raining = Yes AND is_snowing = Yes (meant to need either)		FNOT (is_logged_in = Yes)

Definitions

age >= 13 AND has_permission = Yes

Fill in the Blanks

Complete each line of code by filling in the missing parts.

Decision: age >= 13 ___ permission = Yes

Diamond A: member = Yes? Yes -> Discount Diamond B: coupon = Yes? Yes -> Discount One: member = Yes __ coupon = Yes

Decision: ___ is_raining

Diamond 1: age >= 13? Yes -> Diamond 2 Diamond 2: permission = Yes? Yes -> Enter One diamond: age >= 13 ___ permission = Yes

Decision: temp < 10 __ temp > 35

Spot the Error

Shade in the letter of the line that contains an error.

Question 1

A Diamond: age>=13 AND perm=Yes

B Diamond: age>=13 OR perm=Yes

C No -> Print Entry denied

D Rule: needs BOTH conditions

Question 2

A Diamond A: age >= 13?

B A Yes -> Diamond B: perm=Yes?

C B No -> Print Allowed

D Any No -> Print Denied

Question 3

A Diamond A: student=Yes?

B A Yes -> Print Discount

C A Yes -> Diamond B: age>=65?

D B Yes -> Print Discount

E B No -> Print Full price

Question 4

A Input is_raining

B Diamond: is_raining = Yes?

C Yes -> Print Go outside

D No -> Print Take umbrella

Question 5

A Input temp

B Diamond: temp>=18 AND temp<=25

C Yes -> Print Too hot or cold

D No -> Print Too hot or cold

Answer Key

Logical operators in a flowchart decision

Section A: Quick Questions

A — One diamond: has_ticket = Yes AND paid = Yes

B — Two diamonds in a row, where the Yes path of the first leads into the second

B — True

A — When at least one part is true

A — Both diamonds have a Yes path that joins the same outcome

Section B: Match the Pairs

age >= 13 AND has_permission = Yes → One diamond that sends the flow down Yes only when both parts are true

is_weekend = Yes OR is_holiday = Yes → One diamond that sends the flow down Yes when at least one part is true

Two diamonds in a row, where both answers must be Yes to reach the action, can be replaced by one AND diamond → score >= 50 AND attendance >= 80

NOT reverses a question so the Yes path is taken when the original answer would have been No → NOT (is_logged_in = Yes)

Diamond: age >= 13 OR has_permission = Yes (meant to need both) → OR was used when both conditions must be true. It should be AND, because OR lets someone through with only one part true.

Diamond: is_raining = Yes AND is_snowing = Yes (meant to need either) → AND was used when only one condition needs to be true. It should be OR, because AND needs both to be true at once.

Section C: Definitions

age >= 13 AND has_permission = Yes — A combined condition in one decision diamond. AND needs both parts true, OR needs just one, NOT reverses it. One diamond with AND matches two diamonds in a row.

Section D: Fill in the Blanks

Decision: age >= 13 AND permission = Yes

Diamond A: member = Yes? Yes -> Discount
Diamond B: coupon = Yes? Yes -> Discount
One: member = Yes OR coupon = Yes

Decision: NOT is_raining

Diamond 1: age >= 13? Yes -> Diamond 2
Diamond 2: permission = Yes? Yes -> Enter
One diamond: age >= 13 AND permission = Yes

Decision: temp < 10 OR temp > 35

Section E: Spot the Error

B — The rule says both conditions are needed, so the diamond must use AND. With OR, someone aged 13 or over with no permission would still be allowed in.

C — Two diamonds in a row work like AND. You are only allowed if both answers are Yes, so the Yes path of diamond B leads to Allowed. It should be 'B Yes -> Print Allowed'.

C — Line 2 already sends A Yes to Discount. Diamond B should only be reached from the A No path, so this line should be 'A No -> Diamond B: age>=65?'. Together the two Yes paths work like 'student=Yes OR age>=65'.

B — The Yes path prints 'Go outside', so the question must be reversed with NOT. It should be 'Diamond: NOT is_raining = Yes?'. Without NOT, Yes would mean it is raining.

C — When temp is between 18 and 25 both parts of the AND are true, so the Yes path should print 'Comfortable'. Both paths printing the same message means Comfortable would never appear.