<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
3 1/2 miles = 7/2 miles
1/2 hours= 30 minutes
So,
In 30 mins, travelled 7/2 miles
In 1 min, travelled 7/2 ÷ 30= 7/2× 1/30 = (7×1)/(2×30) = 7/60 miles
In 60 mins, travelled (7×60)/60 miles = 420/60 miles = 7 miles.
Hence, the speed is 7 miles per hour.
We can start with subtracting 7040 from 20,000, getting us 12960 gallons remaining, If 720 gallons per hour are coming, we can make the equation 12960 = 720h, with h as hours. Next, we can divide both sides by 720, getting us 18. It will take 18 hours to fill the pool.
2/8 of an hour is 15,and 2/6 of an hour is 20 minutes. 20-15 is 5 minutes
