How many feet are in 4725 miles

How many terms are there in a geometric series if the first term is 4, the common ration is 3 and the sum of the series is 160

Marina CMI [18]

$\bf \qquad \qquad \textit{sum of a finite geometric sequence}
\\\\
S_n=\sum\limits_{i=1}^{n}\ a_1\cdot r^{i-1}\implies S_n=a_1\left( \cfrac{1-r^n}{1-r} \right)\quad 
\begin{cases}
n=n^{th}\ term\\
a_1=\textit{first term's value}\\
r=\textit{common ratio}\\
----------\\
a_1=4\\
r=3\\
S_n=160
\end{cases}$

$\bf 160=4\left( \cfrac{1-3^n}{1-3} \right)\implies 160=4\left( \cfrac{1-3^n}{-2} \right)\implies 160=-2(1-3^n)
\\\\\\
160=2(3^n-1)\implies \cfrac{160}{2}=3^n-1\implies 80=3^n-1
\\\\\\
81=3^n~~
\begin{cases}
81=3\cdot 3\cdot 3\cdot 3\\
\qquad 3^4
\end{cases}\implies 3^4=3^n\implies 4=n$

3 0

3 years ago

Original price of a pen $1.99 tax:6%

egoroff_w [7]

Answer:

The final price would be 2.11$

5 0

3 years ago

Kasey needs 1.5 cups of milk and 4 cups of sugar to make 12 muffins. She plans to make 36 muffins . How many fl oz of sugar does

Masja [62]

Answer:

12 cups of milk

Step-by-step explanation:

36/12= 3

4 x 3= 12

So the Answer is 12 cups of milk

4 0

3 years ago

A certain four-cylinder combination lock has 50 numbers on it. to open it, you turn to a number on the first cylinder, then t

kumpel [21]

A certain four-cylinder combination lock has 50 numbers on it.

It is a four cylinder combination lock

Each cylinder has 50 numbers

So we have to choose 4 numbers for 4 cylinders

_____ , ______ , ______, _____

you turn to a number on the first cylinder

We have 50 numbers so we have 50 combinations

__50___ , ______ , ______, _____

Repetitions are allowed so we do the same for remaining three

50 , 50 , 50 , 50

50 * 50 * 50* 50 = 6250000

There are 6250000 different lock combinations .

7 0

3 years ago

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Given and which statement is correct? AB = FD AB < FD AB > FD AB ≤ FD

mojhsa [17]

Side AB is longer than side FD. Option (b) is correct.

Further explanation:

Given:

The options area as follows,

(a). $\overline {{\text{AB}}}$ and $\overline {{\text{FD}}}$ are the same length.

(b). $\overline {{\text{AB}}}$ is longer than $\overline {{\text{FD}}}.$

(c). $\overline {{\text{AB}}}$ is shorter than $\overline {{\text{FD}}}.$

(d). ${\text{AB}} \leqslant {\text{FD}}$

Explanation:

The sides opposite to equal angles are equal.

The side opposite to greater angle is greater than the other one.

The measure of $\angle {\text{DEC}}$ is ${65^ \circ }.$

The measure of $\angle {\text{BCA}}$ is ${72^ \circ }.$

$\angle {\text{BCA}}$ is greater than $\angle {\text{DEC}}$ . Therefore, the side opposite to greater angle is greater.

Side AB is longer than side FD. Option (b) is correct.

Option (a) is not correct.

Option (b) is correct.

Option (c) is not correct.

Option (d) is not correct.

Learn more:

Learn more about inverse of the function brainly.com/question/1632445.
Learn more about equation of circle brainly.com/question/1506955.
Learn more about range and domain of the function brainly.com/question/3412497.

Answer details:

Grade: High School

Subject: Mathematics

Chapter:Triangles

Keywords: relations, functions, all relation are functions, all functions are relations, no relations are functions, no functions are relation, one-to-one, onto, graph representation, paired, y-value, x-values, origin.

3 0

3 years ago

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