Express the Sum Using Summation Notation with a Lower Limit $$\frac { 4 } { 5 } + \frac { 5 } { 6 } + \frac { 6 } { 7 } + \frac { 7 } { 8 } + \ldots + \frac { 17 } { 18 }$$

question 40

Multiple Choice

Express the sum using summation notation with a lower limit of summation not necessarily 1 and with k for the index of
summation.
- $$\frac { 4 } { 5 } + \frac { 5 } { 6 } + \frac { 6 } { 7 } + \frac { 7 } { 8 } + \ldots + \frac { 17 } { 18 }$$

• A) \(\sum _ { k = 5 } ^ { 17 } \frac { k } { k + 1 }\)
• B) \(\sum _ { k = 4 } ^ { 17 } \frac { k + 1 } { k }\)
• C) \(\sum _ { k = 4 } ^ { 17 } \frac { k } { k + 1 }\)
• D) \(\sum _ { \mathrm { k } = 4 } ^ { 17 } \frac { \mathrm { k } } { \mathrm { k } \cdot 1.5 }\)

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Definitions:

Hippocampus

A region of the brain that is associated with memory formation, organization, and storage.

Cerebellum

A region of the brain that plays an important role in motor control, coordination, precision, and accurate timing.

Decay Theory

A theory suggesting that memory fades and disappears over time if it is not accessed and used.

Forgetting

The loss or decline of memory over time, which can occur for various reasons including decay, interference, and retrieval failure.