Question

How do I find the first term of geometric progression when the ration is 2 and the sum of the first 6 terms is 7?​

Answer 1

• The first term is 1/9

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Let the first term be a.

The common ratio is r = 2 and the sum of the first 6 terms is S₆ = 7.

Use the sum of first n terms formula:

• Sₙ = a(rⁿ - 1)/(r - 1)

Substitute and solve for a:

• 7 = a(2⁶ - 1)/(2 - 1)
• 7 = a(64 - 1)/1
• 7 = 63a
• a = 7/63
• a = 1/9