Question 821174
Being less than 100, he has 2 digits in his age
Let the tens digit = {{{ t }}}
Let the units digit = {{{ u }}}
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given:
{{{ 10t + u = 6*( t + u ) }}}
{{{ 10t + u = 6t + 6u }}}
{{{ 4t = 5u }}}
The only digits that satisfy this:
{{{ t = 5 }}}
{{{ u = 4 }}}
He is 54
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check:
{{{ 54 = 6*( 5 + 4 ) }}}
{{{ 54 = 6*9 }}}
{{{ 54 = 54 }}}
OK