Question 1143537
Use normal approximation
mean is np=.30*20=6
variance is np(1-p)=6*0.70=4.2
sd is sqrt (V)=2.05
greater than 7 using continuity correction factor of 7.5
z>(7.5-6)/2.05 or z> 0.73
0.2327 is probability 

calculator gives 0.2277 for exact answer.