Step-by-step explanation:
fill in the missing fraction parts
Answer:
The answer is below
Step-by-step explanation:
1)
mean (μ) = 12, SD(σ) = 2.3, sample size (n) = 65
Given that the confidence level (c) = 90% = 0.9
α = 1 - c = 0.1
α/2 = 0.05
The z score of α/2 is the same as the z score of 0.45 (0.5 - 0.05) which is equal to 1.65
The margin of error (E) is given as:

The confidence interval = μ ± E = 12 ± 0.47 = (11.53, 12.47)
2)
mean (μ) = 23, SD(σ) = 12, sample size (n) = 45
Given that the confidence level (c) = 88% = 0.88
α = 1 - c = 0.12
α/2 = 0.06
The z score of α/2 is the same as the z score of 0.44 (0.5 - 0.06) which is equal to 1.56
The margin of error (E) is given as:

The confidence interval = μ ± E = 23 ± 2.8 = (22.2, 25.8)
Answer:
21 matches
Step-by-step explanation:
This is a combination problem where we have to select two member out of 7 members
So we want calculation of 7C2
7C2 = 7!/[(2!)(7-2)!]
(7*6*5*4*3*2*1)/[(2*1) *(5*4*3*2*1]
(7*6)/2 ~ Note everything that easily cancels here!
42/2
21 matches
Answer:
Step-by-step explanation:
Speed = distance travelled/time
A horse ran 800 m in 40 seconds. This means that the speed is
800/40 = 20 m/s
The horse ran 1200 m in 60 seconds. This means that the speed is
1200/60 = 20 m/s
The horse ran 1200 m in 60 seconds. This means that the speed is
480/24 = 20 m/s
Since the horse's rate or speed is the same at each scenario, it means that the relationship between the distance covered by the horse and the time taken is proportional.
Let k represent the constant of proportionality. The constant of proportionality is 20. It represents speed of the horse.
Let d represent the distance in meters.
Let t represent the time in seconds.
Therefore
d = 20t
Answer:
25 meters
Step-by-step explanation:
30 km/hr = (30 km/1 hr)*(1000 m/1 km)*(1 hr/60 min)*(1 min/60 sec)
30 km/hr = (30*1000*1*1)/(1*1*60*60) meters per second
30 km/hr = 8.3333333333 m/s (approximate)
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The speed or rate is r = 8.3333333333 meters per second approximately, and the time is t = 3 seconds, so,
distance = rate*time
d = r*t
d = 8.3333333333 * 3
d = 24.9999999999
Due to rounding error, the true answer should be d = 25. We can see this if we opted to use the fraction from of 8.3333... instead of the decimal representation which isn't a perfect exact measurement.