Big Idea 3: Algorithms and Programming · Topic 3.6 · Coding Practice
Conditionals — Code It Yourself
Write real code and check it against the expected output. Pick Python or JavaScript; the AP pseudocode reference is there when you need it.
You warmed these up on paper in Trace the Gate and Write the Rule, hand-tracing which branch runs. Now type and run the same gate scenario for real — the problems get harder as you go, from a single IF to an IF-ELSE with a computed condition, ending with one you build from scratch. Evaluate the condition first, predict the output, then check yourself, hardest last.
Problem 1 of 4
A rider is 52 inches tall. Write an IF that displays exactly Board the ride when height is at least 48. (For 52, it should print.)
Use >= for 'at least': the condition height >= 48 is true for 52, so the block runs. Put the print inside the IF so it only runs when the condition is true.
Problem 2 of 4
A rider is 45 inches tall. Write an IF-ELSE: display Board the ride when height is at least 48, otherwise display Grow a bit more. (For 45, it should print the second message.)
Expected output: Grow a bit more
Show AP pseudocode reference
height ← 45
IF(height ≥ 48)
{
DISPLAY("Board the ride")
}
ELSE
{
DISPLAY("Grow a bit more")
}
Evaluate the condition first: 45 >= 48 is false, so the ELSE block runs. The ELSE has no condition of its own — it catches every case the IF did not make true.
Problem 3 of 4
A group ticket costs 12 dollars per person for a group of 4. Compute the total, then display Group discount applies when the total is at least 40, otherwise display No discount.
First do the arithmetic: total = 12 * 4 = 48. Then the condition total >= 40 is true, so the IF block runs. A condition can be a computed value, not just a bare variable.
Problem 4 of 4
Build from scratch: a rider is 47 inches tall. First display Welcome! on its own line, then use an IF-ELSE to display Board the ride when height is at least 48, otherwise Grow a bit more. Two lines of output.
Expected output: Welcome!
Grow a bit more
Show AP pseudocode reference
height ← 47
DISPLAY("Welcome!")
IF(height ≥ 48)
{
DISPLAY("Board the ride")
}
ELSE
{
DISPLAY("Grow a bit more")
}
The greeting runs before the decision, so it prints every time. Then evaluate 47 >= 48: it is false, so the ELSE runs. Order matters — the sequential line prints first, then exactly one branch of the IF-ELSE.
Your code runs on a secure external service. Answers are checked automatically — nothing is stored.
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