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3 years ago

If a1= 7 and r=3, find a4

Mathematics

1 answer:

9966 [12]3 years ago

7 0

Answer:

a4 = 189

Step-by-step explanation:

Geometric sequence:

In a geometric sequence, the quotient r between consecutive terms is always the same.

The nth term of the sequence is given by:

$a_n = a_1*r^{n-1}$

In which $a_1$ is the first term.

In this question:

$a_1 = 7, r = 3$

The fourth term is:

$a_4 = 7*3^3 = 189$

a4 = 189

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