lesson
Assignment changes stored state
1 · Learn
In Python, score = 4 assigns the value 4 to the name score. Then score = score + 3 evaluates the right side using the current value and assigns the resulting 7. This is an update, not a mathematical claim that a number equals itself plus three.
A name should describe its role. Assignment uses =, while equality testing uses ==. Confusing them changes whether you update a value or ask a question about it.
2 · Worked example
After score = 4 and score = score + 3, print(score) displays 7. A later score = 0 resets it rather than subtracting only one point.
3 · Your turn
A variable count is 2, then count = count * 5 runs. What value is stored?
Check your answer
10.
4 · Apply your learning
Trace a short sequence of assignments in a table, then run it and compare each stored value.
Adult guidance and safety
Use an approved private programming or authoring environment and fictional data. Do not install unknown software or enter personal credentials for these exercises. Trace first, then run and test where a suitable tool is available; these text examples do not themselves provide an executable assessment environment.
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Check a calculation · Year 5 onward
Use this only when your teacher or adult allows a calculator for the task. Show your thinking first. It does not replace mental or written arithmetic and does not mark your lesson answer.
Powers, roots and trigonometry · Year 7 onward
Use only when the task allows a calculator. Choose one operation at a time and record your working. Trigonometry here always uses degrees (DEG), not radians. Inverse sine, cosine and tangent return an angle, not a reciprocal. Keep exact fractions and π in answers when requested.
Approximate numerical results use up to 12 significant digits. Inverse sine returns −90° to 90°, inverse cosine 0° to 180°, and inverse tangent −90° to 90°; these are principal values, not every possible solution of a trigonometric equation.
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