a)
Boris knowledge test z score = [ 57 -60 ] / 4.3 = -.69 [ ≈ 24th percentile ]
Boris aptitude test z score = [ 106 -110] / 7.1 = -.56 [ ≈ 28th percentile ]
He did better on the aptitude test
b)
Callie knowledge test z score = [ 63 - 60] / 4.3 = .69 [ ≈ 75th percentile ]
Callie aptitude test z score = [ 114 - 110 ] / 7.1 = .56 [ ≈ 71st percentile]
She did better on the knowledge test
c) -0.93 = [≈ 17th percentile ]
He still did the best on the aptitude test