6x+4 (H)
.........................
Answer:
95% z-confidence interval for the proportion of all children enrolled in kindergarten who attended preschool is between a lower limit of 0.528 and an upper limit of 0.772.
Step-by-step explanation:
Confidence interval = p + or - zsqrt[p(1-p) ÷ n]
p is sample proportion = 39/60 = 0.65
n is the number of children sampled = 60
Confidence level (C) = 95% = 0.95
Significance level = 1 - C = 1 - 0.95 = 0.05
Divide significance level by 2 to obtain critical value (z)
0.05/2 = 0.025 = 2.5%
z at 2.5% significance level = 1.96
zsqrt[p(1-p) ÷ n] = 1.96sqrt[0.65(1-0.65) ÷ 60] = 1.96sqrt[0.2275 ÷ 60] = 1.96sqrt(3.792×10^-3) = 1.96×0.062 = 0.122
Lower limit = p - 0.122 = 0.65 - 0.122 = 0.528
Upper limit = p + 0.122 = 0.65 + 0.122 = 0.772
95% confidence interval is between 0.528 and 0.772
Answer:
The answer is -2.
Step-by-step explanation:
The answer is -2 because the question is asking what -1/3 minus 1 2/3. Let's put this as an improper fraction. You will have -1/3 minus 5/3. When you subtract it, you get -6/3 which is the same as -2. I hope this helps!
In the question, it is given that
Suppose two trains leave a certain station, at the same time, traveling in opposite directions. one train travels 10 mph faster than the other. in 2.5hours, the trains are 255 miles apart.
Let the speed of the slower train be x m/h and faster train be (x+10) m /h.
Distances travelled by them are

And total distance is 255 miles, that is

So the speed of slower train is 46 MPH and of faster train is 56MPH.
We can solve the equation to find it's number of solutions, but we already know it only has 1 solution because it is a linear equation (y is raised to the first power).
3y + <span>5 − 2y = 11
</span>y + <span>5 = 11
</span>y = 6
This confirms that there is only 1 solution.