All categories

3 years ago

the 2nd term in a geometric sequence is 20 the 4th term in the same sequence is 45/4 or 11.25 what is the common ratio?

2 answers:

5 0

Let x be the common ratio and y be the 3rd term

11.25/x=y This means the fourth term divided by the common ratio will get the third term
20x=y This means the second term multiplied by the common ratio will get the third term

11.25/x=20x Set the two y's equal to each other, and solve for x!
20x^2=11.25
x^2=.5625
x=+-√.5625
x=.75 or -.75

navik [9.2K]3 years ago

3 0

__ , 20, __, 11.25

11.25 = 20 * r^(3-1)
11.25/20 = r^2
0.5625 = r^2
sqrt 0.5625 = r
0.75 = r...so common difference is 0.75 or 3/4

You might be interested in

What is the greatest possible percent error in calculating the volume of a box measured to the nearest inch with sides of 5 in,

Otrada [13]

You can't make any errors or else you will get the wrong answer

6 0

2 years ago

A flower grows 6 centimeters in 2 months.<br> How many centimeters does it grow in one<br> week?

noname [10]

1 centimeter every other week.

7 0

2 years ago

Read 2 more answers

1-i need to mix 25% mineral spirits to the varnish i am using what ratio of spirit to varnish am i using? 2-if i use 240 ml of v

zhenek [66]

Answer:

(1) The required ratio of spirit to varnish is 1:3.

(2) You need 80 ml of mineral spirit.

(3) The ratio of tapestries' heights to width is 3:2.

Step-by-step explanation:

(1) If you need to mix 25% mineral spirit to the varnish, then the solution would contain 25% mineral spirit and 75% varnish.

So, $\frac{spirit}{varnish}=\frac{25}{75}$

$=\frac{1}{3}$

Thus, The required ratio of spirit to varnish is 1:3.

(2) If you use 240ml of varnish, then this quantity is 75% of the total solution or ration of varnish to the total solution will be 3:4.

Let $x$ be the quantity of total solution.

Then, $240:x=3:4$ .

⇒ $\frac{240}{x}=\frac{3}{4}$

⇒ $3x=240*4$

⇒ $x=\frac{240*4}{3}$

⇒ $x=320$

That is, total solution is 320 ml.

Now, Spirit = Total solution - Varnish

⇒Spirit = 320ml-240ml

⇒Spirit = 80ml

Hence, if you use 240 ml of varnish, you need 80 ml of mineral spirit.

(3) Robison's tapestries all measure 1.5m long and 1m wide. First, we express dimensions in whole numbers by multiplying them by 10.

Then, dimensions are 15m long and 10m wide.

Now, Height : Width = 15:10

⇒ $\frac{Height}{Width} =\frac{15}{10}$

⇒ $\frac{Height}{Width} =\frac{3}{2}$

Hence, the ratio of tapestries' heights to width is 3:2.

8 0

3 years ago

In a unit circle, ø = 2pi radians What is the terminal point?

BlackZzzverrR [31]

Answer:

The terminal point is (1, 0) ⇒ D

Step-by-step explanation:

In the unit circle, Ф is the angle between the terminal side and the positive part of the x-xis.

The terminal point on the positive part of the x-axis is (1, 0),which means Ф = 0° or 360° and cosФ = 1, sinФ = 0

The terminal point on the positive part of the y-axis is (0, 1),which means Ф = 90° and cosФ = 0, sinФ = 1

The terminal point on the negative part of the x-axis is (-1, 0),which means Ф = 180° and cosФ = -1, sinФ = 0

The terminal point on the negative part of the y-axis is (0, -1),which means Ф = 270° and cosФ = 0, sinФ = -1

In a unit circle

∵ Ф = 2π radians

∵ 2π radians = 360°

→ By using the 1st rule above

∴ The terminal point is (1, 0)

5 0

2 years ago

What is the value of StartFraction 6 Over x EndFraction + 2x2, when x = 3?

Shalnov [3]

<h2>The value of StartFraction 6 Over x EndFraction + 2x2, when x = 3 is 20.</h2>

Explanation:

The given expression is $\frac{6}{x}+2x^2\\$

When x = 3, the expression becomes $\frac{6}{3}+2(3)^2$

$2+2\times9$

= 2 + 18 = 20

4 0

3 years ago

Read 2 more answers