4. The 6th term of an arithmetic series is 13, the sum of the first 40 terms is 3420. Find the sum of the first 30 terms.

Q: What would be the easy way to figure out the 100th and nth of the sequence:  1, 4, 9, 16, 25, 36,.

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Q: 1 4. (2n)" 5. 3"-1 n(n+1)(n+2) 6.

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Q: - 12,800, 6,400, - 3,200, 1,600, ..... Select one:

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Q: Find the sum of the first ten terms of the arithmetic series A1=7, d=-3

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Q: 7. In a geometric series, t5 = 23, 17 = 92. Find the sum of the first 10 terms.

A: As we know that nth term of a GP( An ) = arn-1sum of nth terms ( Sn ) = a( rn - 1 )( r - 1 )

Q: What is the 7th term of the geometric sequence where a₁ = -4,096 and a = 64?

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Q: What is the explicit formula for the sequence if at 8 am a hospital patient has 100 mg of a…

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Q: find the sum of the first 25 terms of an arithmetic series if t12=-26 and t22=-46

A: We need to find the sum of first 25 terms of an Arithmetic series. We have t12=-26   and   t22=-46