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3 years ago

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The simple formula for the nth term of an arithmetic sequence is an = 5n + 15. What is the explicit formula corresponding to the

simple formula?
A. an = 15 + 5n
B. an = 15 + (n - 1)(5)
C. an = 20 + (n)/(5)
D. an = 20 + (n - 1)(5)
E. an = 5 + (n - 1)(15)

1 answer:

Nikitich [7]3 years ago

7 0

Sequence will look like this:
Term 1: 20 --------- 20 + 5(0)
Term 2: 25 --------- 20 + 5(1)
Term 3: 30 --------- 20 + 5(2)
Term 4: 35 --------- 25 + 5(3)
ETC.

It cab noted that the numbers in the bracket (that is, 0, 1, 2, 3, 3, etc) = n-1

Then, the explicit formula will be;
an = 20 + 5(n-1).

The correct answer is D.

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Step-by-step explanation:

1) A lawyer has found 60 investors for a limited partnership to purchase an inner-city apartment building, with each contributing either $4,000 or $8,000. If the partnership raised $348,000, then how many investors contributed $4,000 and how many contributed $8,000?

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y is the number of investors that contributed 8,000.

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Solving the system:

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8 0

3 years ago