Use the general formula of the probability theory P(A or B) = P(A) + P(B) - P(A and B). Substitute the given values to get 0.85 = 0.61 + 0.31 - P(calculus AND scholarship). It implies P(calculus AND scholarship) = 0.61 + 0.31 - 0.85 = 0.07 = 7%. ANSWER