Answer: the speed of the plane is 130 mph
Step-by-step explanation:
Let x represent the speed of the plane. If the car travels 80 mph slower than the plane, then the speed of the car would be (x - 80) mph.
Time = Distance/speed
plane can fly 520 miles in the same time as it takes a car to go 200 miles. This means that the time it takes the plane to fly 520 miles is
520/x
Also, the time it takes the car to drive 200 miles is
200/(x - 80)
Since the time is the same, it means that
520/x = 200/(x - 80)
Cross multiplying, it becomes
520(x - 80) = 200 × x
520x - 41600 = 200x
520x - 200x = 41600
320x = 41600
x = 41600/320
x = 130 mph
Answer:
Slope = -2
Step-by-step explanation:
x1 y1 x2 y2
(-1 , 9) (2 , 3)
Slope = <u>y2 - y1</u>
x2 - x1
<u>3 - 9 </u>= <u> -6 </u>
2 -(-1) = 3
= -2
Answer:
13 participants.
Step-by-step explanation:
Given that a researcher reports an F-ratio with df = 1, 24 for an independent-measures experiment.
i.e. degrees of treatment between groups =1
and within groups = 24
This implies that there are two groups.
For two groups to have same number of participants, since we get total of degrees of freedom =24+1 =25
Hence total items selected = 26
i.e. each group would have 13 entries
So each treatment had 13 participants.
Answer:
44 hours
Step-by-step explanation:
Topic of this question: Creating and Solving Equations, Rates, and Proportions
<h2>
Method 1: Creating and Solving Equations</h2>
Step 1: Find the amount drilled per hour
To do this, we have to divide the amount drilled by the number of hours it took to drill and find how much is being drilled per hour.
(I know it's a mouthful)
-72ft = 24x, where x is the amount drilled per hour
-72ft ÷ 24 = x
-3ft = x
-3ft per hour
Step 2: Find how many hours it takes to drill to -132 ft
Since we know the rate of drilling per hour, we can divide the target amount by the amount drilled per hour
-132 ÷ -3 = y, where y is the number of hours it takes
44 = y
y = 44
It will take a total of 44 hours to drill to -132 ft
<h2>Method 2: Proportions</h2>
We can set up a proportion like this, where we know that it takes 24 hours to drill 72 ft, but we don't know how long it takes to drill 132 feet
Cross multiply
Simplify
Divide both sides by -72
It will take a total of 44 hours to dig to -132 ft
-Chetan K
Sample size, n = 75
Point estimate, p = 52/75 = 0.693
Z at 99.7% confidence interval ≈ 2.96
Population mean interval = p+/- Z*Sqrt [p(1-p)/n]
Substituting;
Population mean interval = 0.693 +/- 2.96*Sqrt [0.693(1-0.693)/75] = 0.693+/-0.158 = (0.535,0.851) or (53.5%,85.1%)