we know that a₁ = 1, and aₙ = aₙ₋₁ + 2, is another way of saying, we add 2 to get the next term, namely, 2 is the common difference.
![\bf n^{th}\textit{ term of an arithmetic sequence} \\\\ a_n=a_1+(n-1)d\qquad \begin{cases} n=n^{th}\ term\\ a_1=\textit{first term's value}\\ d=\textit{common difference}\\[-0.5em] \hrulefill\\ a_1=1\\ d=2\\ n=7 \end{cases} \\\\\\ a_7=1+(7-1)2\implies a_7=1+12\implies a_7=13](https://tex.z-dn.net/?f=%5Cbf%20n%5E%7Bth%7D%5Ctextit%7B%20term%20of%20an%20arithmetic%20sequence%7D%0A%5C%5C%5C%5C%0Aa_n%3Da_1%2B%28n-1%29d%5Cqquad%0A%5Cbegin%7Bcases%7D%0An%3Dn%5E%7Bth%7D%5C%20term%5C%5C%0Aa_1%3D%5Ctextit%7Bfirst%20term%27s%20value%7D%5C%5C%0Ad%3D%5Ctextit%7Bcommon%20difference%7D%5C%5C%5B-0.5em%5D%0A%5Chrulefill%5C%5C%0Aa_1%3D1%5C%5C%0Ad%3D2%5C%5C%0An%3D7%0A%5Cend%7Bcases%7D%0A%5C%5C%5C%5C%5C%5C%0Aa_7%3D1%2B%287-1%292%5Cimplies%20a_7%3D1%2B12%5Cimplies%20a_7%3D13)
The answer would be 85, here's why
200/x=100/42.5
(200/x)*x=(100/42.5)*x
200=2.3529411764706*x
200/2.3529411764706=x
85=x
x=85
The answer is 2.67 seconds per second when rounded but 2.66666...
The weight of each fish would be multiplied by 10.
Assume the first time, the weight was 800 lb. Since there were 100 fish caught, the weight of each fish would be 800/100 = 8 lb.
This time, however, only 10 fish were caught. The weight would be 800/10 = 80 lb.
80 = 8(10), so the weight is 10 times more.
