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Mensa Brainteasers

Week 41 - Thursday


30 charity workers gave an average of three hours of their time per month doing voluntary work. 

With the success of the project, a further 40 volunteers were recruited and the average hours given per month by all the volunteers rose to eight.

On average how much time did each of the last 40 people spend doing voluntary work?




The answer to this puzzle will be revealed on 14.10.13

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14 Oct 2013
Reveal answer

11 hours and 45 minutes.