Question 1149644
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Algebraic expressions are


    Older age = {{{sum_of_ages/2}}} + {{{difference_of_ages/2}}} = {{{16/2}}} + {{{2/2}}} = 8 + 1 = 9  years,


    Younger age = {{{sum_of_ages/2}}} - {{{difference_of_ages/2}}} = {{{16/2}}} - {{{2/2}}} = 8 - 1 = 7  years.
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