Question 896080
I'll assume that {{{ 0 }}} can't be the
leading digit
The total possible 3-digit numbers, no repetition, is
{{{ 5*5*4 = 100 }}}
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The total possible 3-digit numbers, no repetition,
which are {{{ 400 }}} or greater is:
{{{ 2*5*4 = 40 }}}
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So, The total possible 3-digit numbers, no repetition,
less than {{{ 400 }}} is {{{ 100 - 40 = 60 }}}