The answer is D cuz its a +ve parabola and symmetric to the x axis
Given:
μ = 68 in, population mean
σ = 3 in, population standard deviation
Calculate z-scores for the following random variable and determine their probabilities from standard tables.
x = 72 in:
z = (x-μ)/σ = (72-68)/3 = 1.333
P(x) = 0.9088
x = 64 in:
z = (64 -38)/3 = -1.333
P(x) = 0.0912
x = 65 in
z = (65 - 68)/3 = -1
P(x) = 0.1587
x = 71:
z = (71-68)/3 = 1
P(x) = 0.8413
Part (a)
For x > 72 in, obtain
300 - 300*0.9088 = 27.36
Answer: 27
Part (b)
For x ≤ 64 in, obtain
300*0.0912 = 27.36
Answer: 27
Part (c)
For 65 ≤ x ≤ 71, obtain
300*(0.8413 - 0.1587) = 204.78
Answer: 204
Part (d)
For x = 68 in, obtain
z = 0
P(x) = 0.5
The number of students is
300*0.5 = 150
Answer: 150
2/21, 16/28
Multiply by 2,3,4
10% of 14 =1.4
14-1.4=12.6
6% of 14=0.84
12.6+0.84= 13.45
Answer:
-1772
Step-by-step explanation:
The nth term of an arithmetic sequence is expressed as;
Tn = a+(n-1)d
a is the first term
n is the number of terms
d is the common difference
From the sequence
a = 28
d = 8-28 = -12-8 = -20
n =91(since we are looking for the 91st term)
Substrate
T91 = 28+(91-1)(-20)
T91 = 28+90(-20)
T91 = 28-1800
T91 = -1772
Hence the 91st term is -1772
