Which expression is equivalent to 1/5(150X -80y+50-50X -25y +20)

Which is the correct excel formula for the 80th percentile of a distribution that is n(475, 33)? =norm.dist(80,475,33,1) =norm.inv(0.80,475,33) =norm.s.inv((80-475)/33)?

Identify a1 and r for the geometric sequence an= -256(-1/4) n-1

Adrawer contains 12 identical white socks, 18 identical black socks and 14 identical brown socks. what is the least number of socks you must choose, without looking, to be certain that you have chosen two socks of the same colour?