Question
On 3 March a technician records the mass of a sample as 200 grams.
Each day after that the mass falls by 4% of the previous day's mass.
Find the date on which the recorded mass is first below 140 grams.
[3 marks]
Each day after that the mass falls by 4% of the previous day's mass.
Find the date on which the recorded mass is first below 140 grams.
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Modelled on Cambridge 0580 · May/Jun 2026 · Paper 42 · Q12
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Modelled on Cambridge 0580 · May/Jun 2026 · Paper 42 · Q12
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