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i. Let X be the number of students that come from a rural family out of the ten students selected. We want to find P(X < 2).
P(X < 2) = P(X = 0) + P(X = 1)
P(X = 0) = (0.55)^10 = 0.0018
P(X = 1) = 10C1 * (0.45)^1 * (0.55)^9 = 0.0276
Therefore, P(X < 2) = 0.0018 + 0.0276 = 0.0294
ii. Let Y be the number of students that come from a rural family out of the seven students selected. We want to find P(Y > 1).
P(Y > 1) = 1 - P(Y ≤ 1) = 1 - (P(Y = 0) + P(Y = 1))
P(Y = 0) = (0.55)^7 = 0.0138
P(Y = 1) = 7C1 * (0.45)^1 * (0.55)^6 = 0.0761
Therefore, P(Y > 1) = 1 - (0.0138 + 0.0761) = 0.9101