Answer:
Justin travels 211.83 miles on 8.2 gallons of gas.
Step-by-step explanation:
77.5 miles / 3.1 gallons = x miles / 8.2 gallons
Solve for x... multiply by 8.2 gallons on both sides (that cancels it on the right) side of the equation.
8.2 gallons *77.5 miles / 3.1 gallons = x
635.5/ 3.1 = x
211.83 miles = x
X=y-bm is the answer you are looking for
Answer:
x = -1±sqrt(5/3)
Step-by-step explanation:
3x^2+6x=2
We will use completing the square
Factor out a 3 on the left
3(x^2 +2x) = 2
Divide each side by 3
3/3(x^2 +2x) = 2/3
(x^2 +2x) = 2/3
2/2 = 1 1^2 =1
Add 1 to each side
(x^2 +2x+1) = 2/3+1
(x+1) ^2 = 2/3 +3/3
(x+1)^2 = 5/3
Take the square root of each side
sqrt((x+1)^2) = ±sqrt(5/3)
x+1 = ±sqrt(5/3)
Subtract 1 from each side
x+1-1 = -1±sqrt(5/3)
x = -1±sqrt(5/3)
Answer:
95% confidence interval for the proportion of internet users who say online groups have helped solved a problem is between a lower limit of (0.65 - 0.9349/√n) and an upper limit of (0.65 + 0.9349/√n).
Step-by-step explanation:
Confidence interval for a proportion is given as p +/- margin of error (E)
p is the proportion of internet users who say online groups have helped solved a problem = 65% = 0.65
Let the number of internet users be represented by n
confidence level (C) = 95% = 0.95
significance level = 1 - C = 1 - 0.95 = 0.05 = 5%
critical value corresponding to infinity degrees of freedom and 5% significance level is 1.96
E = critical value × sqrt[p(1-p) ÷ n] = 1.96 × sqrt[0.65(1-0.65) ÷ n] = 1.96 × sqrt(0.2275 ÷ n) = 1.96×0.477/√n = 0.9349/√n
Lower limit of proportion = p - E = 0.65 - 0.9349/√n
Upper limit of proportion = p + E = 0.65 + 0.9349/√n
95% confidence interval is (0.65-0.9349/√n, 0.65+0.9349/√n)
The answer is 1360.777 grams
