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Which sequence below represents an exponential sequence

A.(2,6,10,14,18...)

B.(3,5,9,16,24..)

C.(4,8,24,96...)

D.(256,64,16,4..)

1 Answer

2 votes

Answer:

D. (256,64,16,4..)

Explanation:

An exponential sequence is one in which a term is gotten by simply multiplying the previous term with a particular fixed number.

They are written in the form:

yₙ = a * r⁽ⁿ ⁻ ¹⁾

Where yₙ = nth term of the sequence

a = first term before of the sequence

r = common ratio

The only option that represents that is option D.

The common ratio, r, is ¼ and the first term, a, is 256.

To get the second term,

y = 256 * ¼⁽² ⁻ ¹⁾ = 256 * ¹/₄ = 64

To get the third term,

y = 256 * ¼⁽³ ⁻ ¹⁾ = 256 * ¹/₄² = 256 * 1/16 = 16

To get the fourth term,

y = 256 * ¼⁽⁴ ⁻ ¹⁾ = 256 * ¹/₄³ = 256 * 1/64 = 4