Question 909253
Let {{{ P }}} = the original principal
{{{ P + .06*P = 12720 }}}
{{{ 1.06P = 12720 }}}
{{{ P = 12720 / 1.06 }}}
{{{ P = 12000 }}}
She invested $12,000
check:
The interest must have been
{{{ 12720 - 12000 = 720 }}}
{{{ .06*12000 = 720 }}}
OK