The first term of this series (a+1) is 1 and the common ratio (r) is -3.
Thus, the explicit formula is a_n = 1*(-3)^(n-1).
Must check this! suppose we try to calculate the 3rd term. Then n = 3.
a_3 = 1*(-3)^(3-1) = (-3)^2 = 9. This is correct.
a) 9 toilet rolls cost $ 4.23
1 toilet roll costs $ x
9x = 4.23 * 1
x= 4.23 / 9
x = 0.47
So in first case one toilet roll costs $ 0.47.
b) 4 toilet rolls cost $1.96
1 toilet roll costs $ x
4x = 1.96 * 1
x = 1.96 / 4
x = 0.49
So in second case one toilet roll costs $ 0.49.
0.47 < 0.49
The toilet roll in first case is cheaper than the toilet roll in second case.
Hope this heps!
Bro... ahahaha the answer is D DDDDDDDDDDDDDDD peace man
Answer:
B: Yes, the participants are grouped by sun exposure, and then both treatments are randomly assigned within each group.
Step-by-step explanation:
Randomized block design is one in which the experimental units are categorized into groups which we call blocks. Thereafter, treatments will be randomly allocated to the experimental units inside each of the blocks.
Now, from the question, we can see that they were grouped in Blocks according to their outdoor activity which is degree of exposure to the sun. Thereafter the individual groups are randomly assigned treatments.
Thus, Option B is correct.