The Rule of the Wason Four-Card Problem Is, "If There

question 57

Multiple Choice

The rule of the Wason four-card problem is, "If there is a vowel on one side, then there is an even number on the other side." Let's say you are presented with A, 8, M, and 13, each showing on one of four cards. To see if the rule is valid, you would have to turn over the cards showing

• A) 8 and M.
• B) A and M.
• C) A and 13.
• D) 8 and 13.

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Definitions:

Examine If Closed

A control logic instruction that checks whether a circuit or contact is closed (i.e., allowing current flow) before executing further actions.

Examine-On Instruction

In PLC programming, an Examine-On Instruction checks if a specified input or condition is true (e.g., if a switch is on) before executing subsequent instructions.

XIC Instruction

An "Examine if Closed" instruction in ladder logic programming, used to check if a contact is virtually closed in a control system.

Normally Open Relay

A type of electrical relay whose contacts are open in its resting state, closing to complete a circuit when activated.