Answer:
A stratified random sampling involves dividing the entire population into homogeneous groups called strata (plural for stratum). Random samples are then selected from each stratum. ... A random sample from each stratum is taken in a number proportional to the stratum's size when compared to the population.
P = 2(L + W)
P = 400
L = W + 40
400 = 2(W + 40 + W)
400 = 2(2W + 40)
400 = 4W + 80
400 - 80 = 4W
320 = 4W
320/4 = W
80 = W.....so the width (W) = 80 yards
L = W + 40
L = 80 + 40
L = 120...and the length (L) = 120 yards
Answer:
x = 20/9
Step-by-step explanation:
We want to write out all of the mixed fractions into improper fraction form. So -2 and 1/9 becomes -19/9 and -4 and 1/3 becomes -13/3. Then we get (-19/9) - (-13/3). The two minus signs together means a positive/plus sign, so we get -19/9 + 13/3. In order to add, we want the denominator to be the same. A common denominator could be 9, so -19/9 + 13(3)/3(3) = -19/9 + 39/9 = 20/9, which is our final answer
Answer:
y = 7
x = 12
Step-by-step explanation:
14x+7y=217, then 14x = 217 - 7y
14x+3y=189, then 14x = 189 - 3y
217 - 7y = 189 - 3y
add 7y to each side of the equation:
4y + 189 = 217
subtract 1890 from each side:
4y = 28
divide both sides by 4:
y = 7
14x + 3(7) = 189
subtract 21 from each side:
14x = 168
divide both sides by 14:
x = 12
Answer:
8 + 2w
Step-by-step explanation:
⇒ Change all signs to addition (subtraction is the same as adding a negative):
5 + 3w + 3 + -w
⇒ Since the expression is now all addition, you can rearrange them in any order. So group the terms together by their type:
5 + 3 + 3w + -w
⇒ Simplify:
8 + 2w
<u>Answer:</u> 8 + 2w
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<em>Hope this helps!</em> :)
