Answer:
r = 225 Mil/h speed of the airplane in still air
Step-by-step explanation:
Then:
d is traveled distance and r the speed of the airplane in still air
so the first equation is for a 4 hours trip
as d = v*t
d = 4 * ( r + 25) (1) the speed of tail wind (25 mil/h)
Second equation the trip back in 5 hours
d = 5 * ( r - 25 ) (2)
So we got a system of two equation and two unknown variables d and
r
We solve it by subtitution
from equation (1) d = 4r + 100
plugging in equation 2
4r + 100 = 5r - 125 ⇒ -r = -225 ⇒ r = 225 Mil/h
And distance is :
d = 4*r + 100 ⇒ d = 4 * ( 225) + 100
d = 900 + 100
d = 1000 miles
Answer choices are on the picture below :)
A.) simple random sampling.
B.) stratified sampling.
C.) systematic random sampling.
D.) cluster sampling.
Answer:
Please help and NO LINKS
Please help and NO LINKSTo conduct a survey about the type of phone service most people in Greenville prefer, 10 different blocks in the neighborhood are chosen. On these 10 blocks, 10 houses are selected at random, and then one resident of each of those houses is interviewed. This type of sampling method is(A)
Step-by-step explanation:
(Ihopethishelps)(BRAINLEISTPLEASE)❤☺️☻♨️
Answer:
Cluster sampling
Step-by-step explanation:
AI-generated answer
The sampling method described in the question is cluster sampling. In cluster sampling, the population is divided into clusters or groups, and then a random sample of clusters is selected. In this case, the blocks in the neighborhood are the clusters.
Here is a step-by-step explanation of why this is cluster sampling:
1. The first step is to divide the population into clusters. In this case, the population is the neighborhood, and the clusters are the different blocks within the neighborhood.
2. Next, a random sample of clusters is selected. The question states that 10 different blocks in the neighborhood are chosen. This means that the researchers randomly selected 10 blocks from the neighborhood.
3. Once the clusters are selected, a sample is taken from each cluster. The question states that on these 10 blocks, 10 houses are selected at random. This means that within each of the 10 selected blocks, 10 houses are chosen randomly.
4. Finally, the residents of each selected house are interviewed. This means that every resident of each of the selected houses is interviewed to gather information about the type of phone service they prefer.
Overall, this sampling method is cluster sampling because the population is divided into clusters (blocks), a random sample of clusters (10 blocks) is selected, and then a sample is taken from each selected cluster (10 houses on each block).
Answer:
20 six cent
30 eight stamp
10 ten cent
2 twenty centep explanation:
The equation of the line that passes through the points (2,1) and (6,-5) is y = -3/2x + 4. This is calculated using the formula for a line y - y1 = m(x - x1) and the formula for slope.
In order to find the equation of the line passing through the points (2,1) and (6,-5), we can use the formula for a line y - y1 = m(x - x1). Here, m is the slope of the line. We can calculate the slope using the formula (y2 - y1) / (x2 - x1). Thus, for the points (2,1) and (6,-5), the slope m is (-5 - 1) / (6 - 2) = -6/4 = -3/2. We can substitute one pair of points and the slope into the line equation. Let's use (2,1). The equation of this line is then y - 1 = -3/2 * (x - 2). Simplifying, we get the equation of the line to be y = -3/2x + 4.
#SPJ2
Answer:
Its b
Step-by-step explanation:
Answer:
Step-by-step explanation: