Question 1018389
Let {{{ x }}} = your age now
{{{ 80 - x }}} = my age now
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The difference in our ages is: 
{{{ 80 - x - x = 80 - 2x }}}
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Now I look at:
" when I was as old as you are."
That means when my age was {{{ x }}}
and you must have been:
{{{ x - ( 80 - 2x ) }}}
{{{ x - 80 + 2x }}} 
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" I'm thrice as old as you were "
{{{ 80 - x = 3*( x - 80 + 2x ) }}}
{{{ 80 - x = 3*( 3x - 80 ) }}}
{{{ 80 - x = 9x - 240 }}}
{{{ 10x = 320 }}}
{{{ x = 32
and
{{{ 80 - x = 48 }}}
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At present:
You are 32
I am 48
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check the answer:
"when I was as old as you are"
when I was 32
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The difference in our ages is: {{{ 48 - 32 = 16 }}}
So, you were {{{ 32 - 16 = 16 }}}
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I am 3 times that age. I am {{{ 48 }}}
{{{ 48 = 3*16 }}}
{{{ 48 = 48 }}}
OK