Question 976820
P( X < 78.6 ) is determined by calculating the z-score
z-score = (78.6 - 66.6) / 3 = 4, therefore
P( X < 78.6 ) = 1.00 or 100%
now 
P( X > or = 78.6 ) = 1.00 - P( X < 78.6 )
P( X > or = 78.6 ) = 1.00 - 1.00 = 0
The student is not telling the truth