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Today Puzzle #565

Puzzle No. 565– Wednesday 11 September

A jar of jam weighs 800g. If the jar half full of jam weighs 480g, find the weight of the jar.

Today’s #PuzzleForToday has been set by David Feather a retired maths education lecturer

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160g

One method involves subtracting the 480g from the 800g giving 320g for the weight of half the jam. Hence 640g is the weight of the jam in a full jar and so the jar weighs 800g- 640g which equals 160g. An alternative method is to double the 480g which tells you that the weight of 2 jars and the jam in a full jar is 960g. Hence again you get the jar weighs 160g.

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