Question

You are given the following sequence:

Answer 1

                    Question No 1

Answer:

7.5 is the 4th term of the sequence $60, 30, 15, 7.5, ...$ .

In other words:   $\boxed{a_4=7.5}$

Step-by-step explanation:

Considering the sequence

$60, 30, 15, 7.5, ...$

As we know that a sequence is said to be a list of numbers or objects in a special order.

so

$60, 30, 15, 7.5, ...$  

is a sequence starting at 60 and decreasing by half each time. Here, 60 is the first term, 30 is the second term, 15 is the 3rd term and 7.5 is the fourth term.

In other words,

$a_1=60$,

$\:a_2=30$,

$a_3=15$, and

$a_4=7.5$

Therefore, 7.5 is the 4th term of the sequence $60, 30, 15, 7.5, ...$ .

In other words:   $\boxed{a_4=7.5}$

                      Question # 2

Answer:

The value of a subscript 5 is 16.

i.e. When n = 5, then h(5) = 16

Step-by-step explanation:

To determine:

What is the value of a subscript 5?

Information fetching and Solution Steps:

• Chart with two rows.

• The first row is labeled n.

• The second row is labeled h of n. i.e. h(n)

• The first row contains the numbers three, four, five, and six.

• The second row contains the numbers four, nine, sixteen, and twenty-five.

Making the data chart

n                  3         4         5         6

h(n)               4         9         16       25

As we can reference a specific term in the sequence by using the subscript. From the table, it is clear that 'n' row represents the input and and 'h(n)' represents the output.

So, when n = 5, the value of subscript 5 corresponds with 16. In other words: When n = 5, then h(5) = 16

Therefore, the value of a subscript 5 is 16.

                        Question # 3

Answer:

We determine that the sequence 33, 31, 28, 24, 19, … is neither arithmetic nor geometric.

Step-by-step explanation:

Considering the sequence

33, 31, 28, 24, 19, …

Lets calculate the common difference 'd' to determine if the sequence is Arithmetic or not.

$\mathrm{Compute\:the\:differences\:of\:all\:the\:adjacent\:terms}:\quad \:d=a_{n+1}-a_n$

$d = 31 - 33 = -2$

$d = 28 - 31 = -3$

$d = 24 - 28 = -4$

$d = 19 - 24 = -5$

As the common difference 'd' is not constant. It means the sequence is not Arithmetic.

Lets now calculate the common ratio 'r' to determine if the sequence is Geometric or not.

$\mathrm{Compute\:the\:ratios\:of\:all\:the\:adjacent\:terms}:\quad \:r=\frac{a_n}{a_{n-1}}$

$\frac{31}{33}=0.93939\dots ,\:\quad \frac{28}{31}=0.90322\dots ,\:\quad \frac{24}{28}=0.85714\dots ,\:\quad \frac{19}{24}=0.79166\dots$

The ratio is not constant. It means the sequence is not Geometric.

From the above analysis, we determine that the sequence 33, 31, 28, 24, 19, … is neither arithmetic nor geometric.

                        Question # 4

Answer:

We determine that the sequence -99, -96, -92, -87, -81... is neither arithmetic nor geometric.

Step-by-step explanation:

From the description statement:

''negative 99 comma negative 96 comma negative 92 comma negative 87 comma negative 81 comma dot dot dot''.

The statement can be translated algebraically as

-99, -96, -92, -87, -81...

Lets calculate the common difference 'd' to determine if the sequence is Arithmetic or not.

$\mathrm{Compute\:the\:differences\:of\:all\:the\:adjacent\:terms}:\quad \:d=a_{n+1}-a_n$

$-96-\left(-99\right)=3,\:\quad \:-92-\left(-96\right)=4,\:\quad \:-87-\left(-92\right)=5,\:\quad \:-81-\left(-87\right)=6$

As the common difference 'd' is not constant. It means the sequence is not Arithmetic.

Lets now calculate the common ratio 'r' to determine if the sequence is Geometric or not.

$\mathrm{Compute\:the\:ratios\:of\:all\:the\:adjacent\:terms}:\quad \:r=\frac{a_n}{a_{n-1}}$

$\frac{-96}{-99}=0.96969\dots ,\:\quad \frac{-92}{-96}=0.95833\dots ,\:\quad \frac{-87}{-92}=0.94565\dots ,\:\quad \frac{-81}{-87}=0.93103\dots$

The ratio is not constant. It means the sequence is not Geometric.

From the above analysis, we determine that the sequence -99, -96, -92, -87, -81... is neither arithmetic nor geometric.    

                     Question # 5

Step-by-step explanation:

Considering the sequence

12, 22, 30, 36, 41, …

$\mathrm{Compute\:the\:differences\:of\:all\:the\:adjacent\:terms}:\quad \:d=a_{n+1}-a_n$

$22-12=10,\:\quad \:30-22=8,\:\quad \:36-30=6,\:\quad \:41-36=5$

As the common difference 'd' is not constant. It means the sequence is not Arithmetic.

$\mathrm{Compute\:the\:ratios\:of\:all\:the\:adjacent\:terms}:\quad \:r=\frac{a_n}{a_{n-1}}$

$\frac{22}{12}=1.83333\dots ,\:\quad \frac{30}{22}=1.36363\dots ,\:\quad \frac{36}{30}=1.2,\:\quad \frac{41}{36}=1.13888\dots$

The ratio is not constant. It means the sequence is not Geometric.

From the above analysis, we determine that the sequence 12, 22, 30, 36, 41, … is neither arithmetic nor geometric.