In a GP, the first term is 5 and the common ratio is 2.

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In a GP, the first term is 5 and the common ratio is 2. The eighth term is —

1. 640
2. 1280
3. 256
4. 160

Correct Option: A

Here , first term a = 5 and the common ratio r = 2. T
According to question,
nth term of a GP = ar^{n – 1}
∴ 8th term = 5 × (2)^{8 – 1} = 5 × (2)⁷
8th term = 5 × 128 = 640
Hence , The eighth term is 640 .