In: Math
1.Given the following sampling distribution:
X | -18 | -13 | -2 | 10 | 19 |
P(X) | 1⁄25 | 9⁄100 | 7⁄100 | 2⁄25 | ___ |
What is P(X = 19)
2. Given the following sampling distribution:
X | -20 | -11 | -7 | 12 | 14 |
P(X) | 1⁄25 | 3⁄100 | 9⁄100 | 1⁄50 | ___ |
What is P(X > -11)?
3.Given the following sampling distribution:
X | -19 | -14 | -3 | 5 | 15 |
P(X) | 1⁄25 | 9⁄100 | 7⁄100 | 2⁄25 | ___ |
What is the mean of this sampling distribution?
Q.1) P(X = 19) = 1 - [(1/25) + (9/100) + (7/100) + (2/25)]
=> P(X = 19) = 1 - [(4/100) + (9/100) + (7/100) + (8/100)]
=> P(X = 19) = 1 - [(4+9+7+8)/100]
=> P(X = 19) = 1 - (28/100)
=> P(X = 19) = 72/100
=> P(X = 19) = 18/25
=> P(X = 19) = 0.72
Q.2) P(X = 14) = 1 - [(1/25) + (3/100) + (9/100) + (1/50)]
=> P(X = 14) = 1 - [(4/100) + (3/100) + (9/100) + (2/100)]
=> P(X = 14) = 1 - [(4+3+9+2)/100]
=> P(X = 14) = 1 - (18/00)
=> P(X = 14) = 82/100
=> P(X = 14) = 0.82
Therefore,
P(X > -11) = P(X = -7) + P(X = 12) + P(X = 14)
=> P(X > -11) = 9/100 + 1/50 + 82/100
=> P(X > -11) = (9/100) + (2/100) + (82/100)
=> P(X > -11) = (9 + 2 + 82) / 100
=> P(X > -11) = 93/100
=> P(X > -11) = 0.93
Q.3) P(X = 15) = 1 - [(1/25) + (9/100) + (7/100) + (2/25)]
=> P(X = 15) = 1 - [(4/100) + (9/100) + (7/100) + (8/100)]
=> P(X = 15) = 1 - [(4+9+7+8)/100]
=> P(X = 15) = 1 - (28/100)
=> P(X = 15) = 72/100
=> P(X = 15) = 18/25
Expected value of X is,
E(X) = [ (-19 * 1/25) + (-14 * 9/100) + (-3 * 7/100) + (5 * 2/25) + (15 * 18/25) ]
=> E(X) = -0.76 - 1.26 - 0.21 + 0.4 + 10.8
=> E(X) = 8.97
Therefore, mean of this sampling distribution is 8.97