Exactly 20 years ago, the mean age of a group of boys was 15.7 years and the

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Exactly 20 years ago, the mean age of a group of boys was 15.7 years and the sum of the squares of their ages was 16000. If the sum of the squares of their ages has increased by 8224 in this 20-year period, find the number of boys in the group.

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Cambridge International AS & A Level Mathematics Probability & Statistics 1 Coursebook

ISBN: 9781108407304

1st Edition

Authors: Dean Chalmers, Julian Gilbey

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Question Posted: Sep 13, 2021 01:55 AM

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Exactly 20 years ago, the mean age of a group of boys was 15.7 years and the

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Cambridge International AS & A Level Mathematics Probability & Statistics 1 Coursebook

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