Question 1171465
a is 12C3(0.27)^3*(0.73^9)=0.2549
b at least 4 look at 3 or fewer, that is 2ndVARSbinomcdf(12,0.27,3)=0.5863; at least 4 is the complement or 04137.
c fewer than 8 is the same with the argument (12,0.27,7)=0.9953