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Today Puzzle #658

Puzzle No. 658 – Tuesday 21 January 2020

A swarm of what appeared to be locusts forced a passenger plane off its course in Africa last week. A large swarm can be up to 50billion locusts! They destroy crops – each eating its own body weight every day. If each locust weighs 2grams and the swarm travels 100km per day, what mass of crops will be lost if a swarm travels the 5000km from North Africa to the UK, as happened in 1954?

Today’s #PuzzleForToday has been set by Dr Shaun Fitzgerald, Fellow of Girton College Cambridge

Click here for the answer

Number of days for the journey = 5000km / 100km per day = 50 days

Mass of crops lost each day = (2/1000 kg per locust) x 50 billion locusts = 100m kg = 100,000 tonnes/day

Total mass of crops lost = 50 days x 100,000 tonnes/day = 5 million tonnes

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