Express the Sum Using Summation Notation A) $\sum _ { k = 1 } ^ { 4 } \frac { 5 ^ { 15 + k } } { 9 ^ { 3 + k } }$

question 156

Multiple Choice

Express the sum using summation notation.
- $$\frac { 5 ^ { 14 } } { 9 ^ { 4 } } + \frac { 5 ^ { 13 } } { 9 ^ { 5 } } + \frac { 5 ^ { 12 } } { 9 ^ { 6 } } + \ldots + \frac { 5 ^ { 7 } } { 9 ^ { 11 } }$$

• A) \(\sum _ { k = 1 } ^ { 4 } \frac { 5 ^ { 15 + k } } { 9 ^ { 3 + k } }\)
• B) \(\sum _ { k = 1 } ^ { 8 } \frac { 5 ^ { - k } } { 9 ^ { 3 + k } }\)
• C) \(\sum _ { k = 1 } ^ { 8 } \frac { 5 ^ { 15 - k } } { 9 ^ { k } }\)
• D) \(\sum _ { k = 1 } ^ { 8 } \frac { 5 ^ { 15 - k } } { 9 ^ { 3 + k } }\)

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Definitions:

Conditioned Reinforcer

A stimulus that gains its reinforcing power through its association with a primary reinforcer.

Operant Behavior

Behavior that is controlled by its consequences, including rewards and punishments, in the context of learning.

Conditioned Reinforcer

A stimulus that acquires the ability to reinforce behavior through its link to a primary reinforcer.

Primary Reinforcer

A naturally reinforcing stimulus, such as food or water, that satisfies a basic biological need.