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Ancestry

A man who is aged between 50 & 70, and has a very large number of grandsons , said 'Each of my sons has as many sons as brothers, and the combined number of my sons and grandsons is exactly my age'. How old is the man and how many grandsons does have?

Please give solution......

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Note by Sharath Chandar
3 years, 4 months ago

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let x be the age of the man

n be the number of sons

no. of brothers for each son = n-1 = no. of sons for each son

=> total no. of grandsons = n*(n-1)

sons + grandsons = age

=> n + n*(n-1) = x

x = n^2

since n is an integer, the only perfect square between 50 and 70 is 64.

=> age = 64

grandsons = 56 Thirupathi Thangavel · 3 years, 4 months ago

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@Thirupathi Thangavel Thank you very much!!!!! Sharath Chandar · 3 years, 4 months ago

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64 and 57 Minmoy Kumar Kundu · 3 years, 4 months ago

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the man is 64 years old and has 56 grandsons Saleem Saif · 3 years, 4 months ago

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@Saleem Saif can u post how how u solved this problem.. Sharath Chandar · 3 years, 4 months ago

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@Saleem Saif please solve the problem Unnati Bindal · 3 years, 4 months ago

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