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Find the 7th term of the geometric sequence whose common ratio is 1/3 and whose first term is 7.

User Helma
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Answer:

the 7th term of the geometric sequence with common ratio 1/3 and first term 7 is 7/729.

Explanation:

The general formula for the nth term of a geometric sequence with first term a and common ratio r is:

an = ar^(n-1)

In this problem, the first term a is 7 and the common ratio r is 1/3. Substituting these values into the formula, we get:

a7 = 7(1/3)^(7-1)

Simplifying the exponent, we get:

a7 = 7(1/3)^6

To evaluate this expression, we can first simplify the denominator by using the fact that (1/3)^2 = 1/9:

(1/3)^6 = (1/3)^2 * (1/3)^2 * (1/3)^2 = (1/9)^3 = 1/729

Substituting this value back into the equation, we get:

a7 = 7(1/729)

Simplifying this expression, we get:

a7 = 7/729

Therefore, the 7th term of the geometric sequence with common ratio 1/3 and first term 7 is 7/729.

User Zhanxw
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