b. Tentukan nilai peluang P ( X ≤ 1) 1 1 + 1 ≤ 1 = 0 ≤ ≤ 1 = න = න 4 0 0 1 1 = න( + 1) 4 0 1 1 1 2 = + 4 2 0 1 1 1 2 2 = 1 + 1 − 0 + 0 4 2 2 1 1 1 = 1 + 1 − 0 + 0 4 2 2 1 1 = + 1 − 0 + 0 4 2 1 3 = − 0 4 2 Jadi nilai peluang 1 3 3 3 = = ≤ 1 = 4 2 8 8