Question 1057390
There are {{{2^4=16}}} possible outcomes.
Look at the ones that have less than 2 tails.
HHHH
HHHT
HHTH
HTHH
THHH
There are 5 of them. So the remainder must all have at least 2 tails.
{{{P=1-5/16}}}
{{{P=11/16}}}