Answer:
Stratified design with color of paper as the blocks
Step-by-step explanation:
The experimental design that this question uses is the stratified design with color of paper as the blocks
A stratified design is one where the population has been divided into strata that are homogeneous. A good number of participants would then be picked for each of the stratum. The homogeneous strata are also known as the blocks and here in this question we have color of paper as the block here.
The students are of different school levels, elementary, high school and middle school. Each of these levels have 100 students. The students in each levels are halved and each half is randomly assigned information on either a white paper or a blue paper.
Answer:
She should ask the people she pulled out first then pull out more and ask them
Plug them in..
1. (7)^2-(-7) = (7)•(7)-(-7)
2. 49-(-7) = 49+7 (if you are subtracting a negative, change the sign to a plus and take out the negative)
3. Add, 56 is your answer
<u>3x-7(4+2x)=-x+2</u> first step is to distribute the -7 into the (4+2x) this is done by multiplying the -7 to the 4 and them doing the same for the 2x
<u>3x-28-14x=-x+2</u> next you combine like terms as in all the x's you do this by adding the -14x and the 3x together
<u>-11x-28=-x+2 </u> next you put all the x's on one side
<u>+x +x</u>
<u>-10x-28=2</u> <u />next you add 28 to both sides to combine your final like terms
<u>+28 +28
-10x=30</u> the last step is to divide -10x and 30
<u>/-10x /-10x
</u><u>x=-3</u>