<h3>
Answer: 17</h3>
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Work Shown:
a1 = 3 = first term
d = 2 = common difference (since we add 2 to each term to get the next one)
Let's compute the nth term.
an = a1 + (n-1)*d
an = 3 + (n-1)*2
an = 3 + 2n-2
an = 2n+1
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To check things so far, we can plug in something like n = 2
an = 2n+1
a2 = 2*2+1
a2 = 5
Showing that the 2nd term is 5, which matches with the sequence given to us
Let's check n = 3
an = 2n+1
a3 = 2*3+1
a3 = 7
That matches as well. I'll let you check the others.
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Plug in n = 8 to find the 8th term
an = 2n+1
a8 = 2*8+1
a8 = 17
The eighth term is 17, which is the final answer.
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You could extend out the given sequence by adding 2 each time until you reach the 8th term
3,5,7,9,11,13,15,17
Though this method is slow if you need to find say the 38th term
I think it’s 3 that’s what I got
Newton's Law of Cooling
Tf=Ts+(Ti-Ts)e^(-kt) where Tf is temp at time t, Ts is temp of surroundings, Ti is temp of object/fluid. So we need to find k first.
200=68+(210-68)e^(-10k)
132=142e^(-10k)
132/142=e^(-10k)
ln(132/142)=-10k
k=-ln(132/142)/10
k≈0.0073 so
T(t)=68+142e^(-0.0073t) so how long until it reaches 180°?
180=68+142e^(-0.0073t)
112=142e^(-0.0073t)
112/142=e^(-0.0073t)
ln(112/142)=-0.0073t
t= -ln(112/142)/(0.0073)
t≈32.51 minutes
Not enough information is given to put an absolute answer it there could be a million reason like d332 nut5 for example