<span> To get an explicit formula, we need to find an expression which gives the n-th term without having to compute earlier terms in the sequence. Looking at the numbers, and from the recursive formula, we see that the sequence is built by subtracting n from the previous term. This is similar to the triangular number sequence 1,3,6,10,15,... which has the explicit formula a_n = n(n+1)/2. In our case we are subtracting n from the previous term, so we multiply by -1/2 instead of 1/2. However, we also need to add a constant term to reproduce the numbers of the sequence. We can write a_1 = -1(2)/2 + c = 8. Therefore, c = 9.
So the explict formula is:
a_n = -n(n+1)/2 + 9</span>
Since there is a ratio of 3:2, there must be five equal parts in the whole...
45/(3+2)=9
So each part is equal to 9 inches.
So the shorter piece is 2(9)=18 inches.
Answer:
a) n = 100
s = 8
Confidence interval = 95%
Z at 95% = 1.96
Confidence interval formula : to
Substitute the values :
Confidence interval : to
Confidence interval : to
b)n = 200
s =11
Confidence interval = 90%
Z at 90% = 1.64
Confidence interval formula : to
Substitute the values :
Confidence interval : to
Confidence interval : to
Answer:
89
Step-by-step explanation:
83-89=172
172 divided by 2