Question 978173
I understand the formula to be {{{P= 90-3t^"2/3"}}} .
That would mean that immediately after students were given a nine-digit number to memorize ( {{{t=0}}} ),
the percentage who remembered it was {{{P= 90-3*0^"2/3"=90-3*1=90-3=87}}}
At 1 hour, {{{t=60}}} , so
{{{P= 90-3*60^"2/3"}}}=  approximately{{{90-3*15.33=about90-46=44}}}