Answer:
Step-by-step explanation:
Given that X, the number of square feet per house is N(mean, 137)
Sample size = 19
Sample mean x bar =1350 sq ft
Since population std dev is given,
std error of sample = 
Since sample size is small, t critical value can be used
df = 18
t value for 80% two tailed = 1.333
Margin of error = ±1.333(std error) = ±
Confidence interval = sample mean ±margin of error
= 
Answer:
2x − 9 and x + 6
Step-by-step explanation:
2x² + 3x − 54
Factor using the AC method.
2 × -54 = -108
Factors of -108 that add up to 3 are +12 and -9.
Divide by 2 and reduce: 12/2 = 6/1, -9/2 = -9/2.
Therefore, the factors are x + 6 and 2x − 9.
Answer:
No, he not correct because he only ran 4 mi
Step-by-step explanation:
If he walks for 6 min out of the 38 min, then he ran for 32 min.
d = rt 1 mi = 8r
r = 1/8 = 1 mi/8 min Since he ran 32 min we have
d = 1/8(32) = 4 mi.
No, he not correct because he only ran 4 mi