Answer:
The teacher randomly divides the class into two groups. One of the groups receives computer-based instruction and the other group receives traditional instruction without computers. After instruction, each student takes a test and the teacher wants to compare the test scores of the two groups.
Step-by-step explanation:
A two sample t-test is used to compared the means of two samples who were exposed to different scenarios and therefore, it helps us to see the difference between these two samples.
In this problem, the teacher is experimenting with a new computer-based instruction. To be able to use the two-sample t-test she would have to have two randomly assigned samples and expose each of these two samples to different scenarios (one would receive a traditional instruction and the other one would receive a computer instruction), and finally she would need to compare the scores in both samples.
Therefore, the correct answer would be b) The teacher randomly divides the class into two groups. One of the groups receives computer-based instruction and the other group receives traditional instruction without computers. After instruction, each student takes a test and the teacher wants to compare the test scores of the two groups.
<u>*Option A is incorrect</u> because the students are only exposed to the lesson using a computer program and therefore they aren't exposed to different scenarios.
<u>*Option C is incorrect</u> because although in this case the teacher uses both traditional and computer methods, there are not two different samples and she only gets the opinion of the students which is not an exact method of getting information on the effectiveness of the computer based method.
Answer:
63.75
Step-by-step explanation:
255 divided by 4
In trigonometry, the right triangle is considered a special triangle because there are derived equations solely for this type. It is really convenient when dealing right triangle problems because it is more simplified courtesy of the Pythagorean theorems. It is derived that the square of the hypotenuse (longest side of the triangle) is equal to the sum of the squares of the other two legs. In equation, that would be c² = a² + b². For this activity, all you have to do is find the sum of the squares in columns a and b. Then, see if this is equal to the square of the values in column c. Let's calculate each row:
Row 1:
3² + 4² ? 5²
25 ? 25
25 = 25
Row 2:
5² + 12² ? 13²
169 ? 169
169 = 169
Row 3:
9² + 12² ? 15²
225 ? 225
225 = 225
Therefore, all of the given values conform to a² + b² = c².
18 ÷ (2/3) = 18 × (3/2) = 18×3/2 = 9×3 = 27
The answer is 27
