I'll try to understand this but I don't really get it because I'm in middle school
Answer:
12x + 2
Step-by-step explanation:
Let the number be represented by x.
Then five times the number = 5*x
Seven times the number = 7*x
Sum of 5 times the number minus -2 = ![\[5*x - (-2)\]](https://tex.z-dn.net/?f=%5C%5B5%2Ax%20-%20%28-2%29%5C%5D)
= ![\[5x +2\]](https://tex.z-dn.net/?f=%5C%5B5x%20%2B2%5C%5D)
Adding seven times the number to this expression yields, ![\[5x+2+7x\]](https://tex.z-dn.net/?f=%5C%5B5x%2B2%2B7x%5C%5D)
![\[= (5+7)x+2\]](https://tex.z-dn.net/?f=%5C%5B%3D%20%285%2B7%29x%2B2%5C%5D)
![\[= 12x+2\]](https://tex.z-dn.net/?f=%5C%5B%3D%2012x%2B2%5C%5D)
So the simplified expression corresponds to 12x + 2.
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.
The question 6 is 2,150 meters question 7 is length 10w+64 meters
Width 25w+49 meters
BC is 8.7
CA is 20
hope this helps
