Bar diagrams can<span> be used to represent single-step problems</span>
Answer: Stratified sampling
Step-by-step explanation:
Stratified sampling is a particular kind of random sampling technique.
Here , the researcher splits the entire population into distinct groups known as strata.
Then he draw a sample by taking participants from each strata and continue his work on sample.
As per given ,
Researcher = Sneha
Strata = Each floor
Since from each floor she randomly selects 2 rooms and inspects them and then takes the average of these scores.
Therefore , Sneha used the Stratified sampling technique.
Find the mean of the first four test scores first.
(Add all numbers in set and divide by how many numbers there are)
81 + 87 + 71 + 89 = 328 / 4 = 82
Then, find the mean with the 85 added as the fifth term.
81 + 87 + 71 + 89 + 85 = 413 / 5 = 82.6
The impact that the 85 had on the mean test score was that the mean/average increased by 0.6.
This can be solve by establishing equations.
let x be the miles mrs. storey drove
y be the miles mr storey drovee
the first equation is
y = 3x
second equation
x + y = 3200
then substitute equation 1
x + 3x = 3200
4x = 3200
x = 800 miles mrs storey drove
y = 3x = 2400 miles mr storey drove
