Answer:
The no. of variations in sign is 3
Step-by-step explanation:
Variation in sign occurs when every single time a negative product is produced by a pair of consecutive terms.
Therefore, the determination of the number of changes in sign in the given sequence is must.
Therefore, we take the product of the pair of consecutive terms as:
= - 3, variation in sign
= - 6, variation in sign
= 10, no sign variation
= - 20, variation in sign
= 24, no sign variation
Answer:
Since the calculated value of z= 2.82 does not lie in the critical region the null hypothesis is accepted and it is concluded that the sample data support the authors' conclusion that the proportion of the country's boys who listen to music at high volume is greater than this proportion for the country's girls.
The value of p is 0 .00233. The result is significant at p < 0.10.
Step-by-step explanation:
1) Let the null and alternate hypothesis be
H0: μboys − μgirls > 0
against the claim
Ha: μboys − μgirls ≤ 0
2) The significance level is set at 0.01
3) The critical region is z ≤ ± 1.28
4) The test statistic
Z= p1-p2/ sqrt [pcqc( 1/n1+ 1/n2)]
Here p1= 397/768= 0.5169 and p2= 331/745=0.4429
pc = 397+331/768+745
pc= 0.4811
qc= 1-pc= 1-0.4811=0.5188
5) Calculations
Z= p1-p2/ sqrt [pcqc( 1/n1+ 1/n2)]
z= 0.5169-0.4429/√ 0.4811*0.5188( 1/768+ 1/745)
z= 2.82
6) Conclusion
Since the calculated value of z= 2.82 does not lie in the critical region the null hypothesis is accepted and it is concluded that the sample data support the authors' conclusion that the proportion of the country's boys who listen to music at high volume is greater than this proportion for the country's girls.
7)
The value of p is 0 .00233. The result is significant at p < 0.10.
Answer:
n = 36
Step-by-step explanation:
54 is a midsegment and is one half the measure of the third side, that is
3n = 2 × 54 = 108 ( divide both sides by 3 )
n = 36
Answer:
99.7%
Step-by-step explanation:
Using the z score formula
z-score is z = (x-μ)/σ
where:
x = raw score
μ = population mean
σ = population standard deviation.
a) for x = raw score = 35
μ = population mean = 44
σ = population standard deviation =3
z = (35 - 44)/3
z = -9/3
z = -3
b) for x = raw score = 53
μ = population mean = 44
σ = population standard deviation =3
z = (53 - 44)/3
z = 9/3
z = 3
We would use the standard normal distribution table to find their probabilities
P(Z<=-3)=0.0013499
P(Z<=+3)=0.99865
So P(-3<=Z<=3)=0.99865 - 0.0013499 = 0.9973
Converting to percentage = 0.9973 × 100 = 99.73%
Therefore, the percentage of auto batteries of this brand that have a life of 35 to 53 months to one decimal place is 99.7%
