Question 198511
{{{l}}}= leah's age
{{{s}}}= Sue's age
{{{j}}}= John's age
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Given:
{{{l = s + 6}}}
{{{j = l + 5}}}
{{{l + s + j = 41}}}
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{{{l = s + 6}}}
{{{l - s = 6}}}
Add to 
{{{l + s + j = 41}}}
{{{l - s = 6}}}
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{{{2l + j = 47}}}
{{{l - j = -5}}}
{{{3l = 42}}}
{{{l = 14}}}
{{{l = s + 6}}}
{{{14 = s + 6}}}
{{{s = 8}}}
{{{j = l + 5}}}
{{{j = 14 + 5}}}
{{{j = 19}}}
Sue is 8 years old
check:
{{{l + s + j = 41}}}
{{{14 + 8 + 19 = 41}}}
{{{41 = 41}}}
OK