Producers in a field fix 20 000 kJ of energy per square metre per year. Primary consumers take in 2 400 kJ and secondary consumers take in 288 kJ. What percentage of the primary consumers' energy reaches the secondary consumers?
Answer and explanation
Correct answer: C. 12%
- Step 1: Divide the secondary consumers' energy by the primary consumers' energy.
- Step 2: 288 ÷ 2400 = 0.12, which is 12%.
Answer
12%.
Why not the others: 1.44%: this is the percentage of the producers' energy. 2%: this is not calculated from these values. 8.3%: this inverts the ratio.
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