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.
Y=3x-10 and 3x+2y=16
y=3x-10
subsitute 3x-10 for y in other equation
3x+2y=16
3x+2(3x-10)=16
distribute
3x+6x-20=16
9x-20=16
add 20 both sides
9x=36
divide both sides by 9
x=4
sub back
y=3x-10
y=3(4)-10
y=12-10
y=2
x=4
y=2
(4,2) is soluiton
9 is the answer
Step by step
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