Answer:
-2x + 1
Step-by-step explanation:
3 + 7x - (2 + 9x)
Distribute the negative:
3 + 7x - 2 - 9x
Combine like terms:
-2x + 1
Answer:
D) 3.28
Step-by-step explanation:
820/x=100/2.5
(820/x)*x=(100/2.5)*x - we multiply both sides of the equation by x
820=40*x - we divide both sides of the equation by (40) to get x
820/40=x
20.5=x
x=20.5
now we have:
2.5% of 820=20.5
Answer:
a)0.6192
b)0.7422
c)0.8904
d)at least 151 sample is needed for 95% probability that sample mean falls within 8$ of the population mean.
Step-by-step explanation:
Let z(p) be the z-statistic of the probability that the mean price for a sample is within the margin of error. Then
z(p)=
where
- Me is the margin of error from the mean
- s is the standard deviation of the population
a.
z(p)=
≈ 0.8764
by looking z-table corresponding p value is 1-0.3808=0.6192
b.
z(p)=
≈ 1.1314
by looking z-table corresponding p value is 1-0.2578=0.7422
c.
z(p)=
≈ 1.6
by looking z-table corresponding p value is 1-0.1096=0.8904
d.
Minimum required sample size for 0.95 probability is
N≥
where
- z is the corresponding z-score in 95% probability (1.96)
- s is the standard deviation (50)
- ME is the margin of error (8)
then N≥
≈150.6
Thus at least 151 sample is needed for 95% probability that sample mean falls within 8$ of the population mean.
Answer:
a = -5
Step-by-step explanation:
6a + 20 = 2a
6a = 2a - 20
4a = - 20
a = -5