So in plain English it's saying if A Is an element of B, then A and B equals A or B. This is true sometimes
Answer:
1) Is more representative
Step-by-step explanation:
The problem with his selection is that maybe there are few students participating in certain sport and those students maybe do quite more excercise than the rest (or quite less). This will modify the results because the sample he selected is biased. This problem wont be solved by method 3 or 4, because he is still selecting students that may modify heavily the results with a high probability
This problem will also appear if he choose a sample by class. Maybe, in a class there are quite few students, and selecting from class will make those students appear quite more often than, lets say, a 7th grade student selected at random, therefore the selection is biased in this case as well.
If he has a list with all seventh grade students, each student is equallly likely to be selected and as a consequence, the the results wont be biased. Approach 1 is the best one.
The equation is 4s=21
You then divide 21 by 4. Because this ends in a decimal the answer cannot be found
Answer: 56in³
Step-by-step explanation:
Let the volume of solid B de denoted as x. Based on the information given in the question, we can solve further by:
1/2 = 28/x
Cross multiply
1 × x = 2 × 28
x = 56
Therefore, the volume of solid is 56in³.
x - 12 = 2
Add 14 to both sides to seperate x from numerical values.
x = 14