Question 1184980
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the age of both lee and Sam is 50 years.
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The meaning is that Lee's age is 50 and Sam's age is 50.  If you really intend to say the SUM of their ages is 50,  then you need to say this unmistakably.  



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 In 5 years time Sam will be 4 times the age of lee.
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Ages y and 50-y;  y for Sam,  50-y for Lee.

{{{y+5=4(50-y+5)}}}
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{{{y+5=4(55-y)}}}
{{{y+5=220-4y}}}
{{{5y=215}}}
{{{y=43}}}
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{{{50-y=50-43=7}}}
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Sam is 43 and Lee is 7.
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