AP CSP 2.1 Exercise 2: Binary Help Desk

Big Idea 2 · Topic 2.1 · Exercise 2

Binary Help Desk

25 minutes - 5 tickets - convert, diagnose, order

Back to the Topic 2.1 lessonAll CSP topics

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The cases, from your handoutNot recorded

The same cases as your handout, in the same order.

Scenario 1 · Foundational

A smart thermostat's install log records the current room temperature as the binary value 10011. The installer needs the decimal temperature to confirm the sensor is reading sanely - and warns that the last trainee reported it as 'ten thousand eleven degrees.'

What this ticket asks (conversion, diagnosis, or ordering) + your predicted answer:

Work shown (place values / repeated subtraction / wrap arithmetic) + final answer or failure mode named:

Enrichment - sub-type or shortcut named (range vs. precision, digit-count, 2^n - 1):

Scenario 2 · Core

A delivery drone must transmit its approved ceiling altitude - decimal 45 meters - to a ground station that accepts only binary. Write the exact bit sequence the drone should send, and prove the sequence decodes back to 45 before it is transmitted.

What this ticket asks (conversion, diagnosis, or ordering) + your predicted answer:

Work shown (place values / repeated subtraction / wrap arithmetic) + final answer or failure mode named:

Enrichment - sub-type or shortcut named (range vs. precision, digit-count, 2^n - 1):

Scenario 3 · Core

A retro arcade cabinet stores the high score in 8 bits. A player sitting at 250 points clears a 15-point bonus and the marquee proudly displays 9. The player files a ticket demanding the missing points back.

What this ticket asks (conversion, diagnosis, or ordering) + your predicted answer:

Work shown (place values / repeated subtraction / wrap arithmetic) + final answer or failure mode named:

Enrichment - sub-type or shortcut named (range vs. precision, digit-count, 2^n - 1):

Scenario 4 · Challenge

A budgeting app adds a $0.10 transit fare to a $0.20 coffee and the running total displays $0.30000000000000004. A one-star review claims the app 'invented money out of nowhere,' and a teammate proposes fixing it by moving the math to a bigger, more expensive processor.

What this ticket asks (conversion, diagnosis, or ordering) + your predicted answer:

Work shown (place values / repeated subtraction / wrap arithmetic) + final answer or failure mode named:

Enrichment - sub-type or shortcut named (range vs. precision, digit-count, 2^n - 1):

Scenario 5 · Challenge

A warehouse sensor network assigns each device a binary priority code: DOOR = 1001, FAN = 110, CAMERA = 1100. A new SIREN must be inserted at decimal priority 22. Order the three existing codes from least to greatest WITHOUT fully converting (name the shortcut used at each step), then write the SIREN's code in binary and state where it lands in the order.

What this ticket asks (conversion, diagnosis, or ordering) + your predicted answer:

Work shown (place values / repeated subtraction / wrap arithmetic) + final answer or failure mode named:

Enrichment - sub-type or shortcut named (range vs. precision, digit-count, 2^n - 1):

No graded check on this page yetNot recorded

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