Answer:
(a) 3, 5 and 6
Step-by-step explanation:
In the experiment, 43 are to be given a gel that contains the tooth-whitening chemicals while the remaining 42 are to be given a placebo. Therefore, a placebo is used.
The 43 that will receive the gel are to be selected randomly.
After the experiment, the whiteness of the two groups will be compared to see the effect of the gel.
Therefore for the experiment to be completely random, 3, 5, and 6 apply.
(b)
For the experiment to be double-blind, the researchers who will evaluate the whiteness and interact with the subjects, and the subjects would not know which subjects received either the whitening gel or the placebo.
I think c if it’s not right lmk
Answer:
C), or y = 200(1.18)^x, because we have 200 bacteria to start with and 1.18 because if you multiply something by 1.18 that is essentially 118% more than the number, or 18% more than the number.
Hope this helps!
25/64 is the answer to your question
Assuming that your question is (x-1)(x+2) = [5(x-1)]/x-1
On the right side, the x-1's will cancel out, leaving you with (x-1)(x+2) = 5
expand the left side, giving you x^2 + x -2 = 5
which goes to x^2 +x -7 = 0
the possible values for x are 2.93 and -3.93. I don't think this was your question, so I'll do the other possible question that you might have been asking.
(x-1)(x+2) = 5(x-1)
divide by x-1 on both sides, leaving you with x+2=5
x+2=5
x=5-3
x=3
.
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