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Plain-English guides to the maths behind everyday calculations, with worked examples and a calculator for every method.
- Plain English Every formula explained
- Worked examples Real numbers, step by step
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Health guides
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Health guides
How Many Calories Do You Need a Day?
Work out your daily calorie needs step by step: BMR with the Mifflin–St Jeor equation, your activity level, and a safe target for losing,…
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Health guides
Understanding BMI: Formula, Categories and Limits
How body mass index is calculated in metric and imperial units, what the adult categories mean, the lower thresholds for Asian populations, and where…