Answer:
- The sum of the series is given as
7/(1 + 7z)
- The series converges for (-1/7, 1/7)
Step-by-step explanation:
Given the geometric series:
7 - 14z + 28z² - 56z³ + ...
The common ratio r is given as
-14z/7 or 28z²/(-14z) or -56z³/(28z²) and so on
r = -7z
The sum of the series is given as
S = a/(1 - r)
Where a is the first term in the series.
S = 7/(1 -(-7z))
= 7/(1 + 7z)
The series converges for |-7z| < 1
That is for -1/7 < z < 1/7
Answer:
=66.501505not9x21−1310.355601no2pt10x12−177.337346not9x11
Step-by-step explanation:
Answer:
4.5 mph or 9/2 mph
Step-by-step explanation:
Let x be the rate of the current
Formula: Distance = rate x time
where rate upstream =(12-x) and time =2 hours
15=(12-x)(2)
15=24–2x
2x=24–15
2x= 9
x=9/2=4.5 miles per hour (rate of current)
Answer:
The probability that a randomly selected person gets incorrect result is 2.2 × 10⁻⁴
Step-by-step explanation:
The parameters given are;
The accuracy of the test for a person who has the respiratory synctial virus = 97%
The accuracy of the test for a person who does not have the respiratory synctial virus = 99%
We have;
a = TP =
b = FP
c = FN
d = TN
a/(a + c) = 0.97
d/(d + b) = 0.99
a/(a + b) = 0.97*0.0055/(0.97*0.0055 + (1 - 0.99)*(1-0.0055))
PPV = 0.349 = 34.9%
Therefore, we have;
a/(a + c) = 0.97 and
a/(a + b) = 0.349
0.97(a + c) =0.349(a + b)
(0.97 - 0.349)a = 0.349·b - 0.97·c
a = (0.349·b - 0.97·c)0.621
b × (1 - 0.0055) = (1 - 0.97)×(1 - 0.0055)
b = 1 - 0.97 = 0.03
Similarly,
c = 1 - 0.99 = 0.01
The proportion of the population that have false positive and false negative = 0.03 + 0.01 = 0.04 = 4%
The probability that a randomly selected person gets incorrect result = 0.04×0.0055 = 0.00022.
