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3 years ago

Find two geometric means between 5 and 135

Mathematics

1 answer:

aniked [119]3 years ago

6 0

Answer:

We are effectively looking for a and b such that 5, a, b, 135 is a geometric sequence.

This sequence has common ratio 3√1355=3, hence a=15 and b=45

Explanation:

In a geometric sequence, each intermediate term is the geometric mean of the term before it and the term after it.

So we want to find a and b such that 5, a, b, 135 is a geometric sequence.

If the common ratio is r then:

a=5rb=ar=5r2135=br=5r3

Hence r3=1355=27, so r=3√27=3

Then a=5r=15 and b=ar=15⋅3=45

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I'm so bad at math please anyone help :(

kondaur [170]

It should be d. , Because if you take the equation 3x+y=9, and make it slope intercept form, it would be y= -3x+9. -3 is the slope, and 9 is the y intercept. D is the answer.

6 0

3 years ago

Suppose you mark n points on a circle, where n is a whole number greater than 1. The number of segments you can draw that connec

leonid [27]

The expression for the number of segments drawn out of the n number of points in the circle is,
n² / 2 - n / 2
Substituting directly to the expression the number of points, n, which is equal to 8,
8² / 2 - 8 / 2 = 28
Thus, there are 28 segments that can be drawn from the points.

5 0

3 years ago

A boat is marked up 20% on the original price. The original price was

pishuonlain [190]

Answer:

Original price was $50 x 0.20 = 10

original price $50 - 10 = $40 the sale price before sales tax

Step-by-step explanation:

hopefully it helps

3 0

2 years ago

A colony of bacteria is grown under ideal conditions in a laboratory so that the population increases exponentially with time. A

Naddik [55]

Answer:

Initial bacterias = 6006000

Altought I believe is safe to assume that the values were 192,000 and 384,000 instead of 192,192,000 and 384,384,000, in that case the initial bacterias is 6000

Step-by-step explanation:

A exponential growth follows this formula:

Bacterias = C*rⁿ

C the initial amount

r the growth rate

n the number of time intervals

Bacterias (55 hours) = 192,192,000

Bacterias (66 hours) = 384,384,000

$Bacterias(55hours)=C*r^{{\frac{55-t}{t}}} \\Bacterias (66hours) = C*r^{\frac{66-t}{t}}}$

If you divide both you can get the growth rate:

$\frac{Bacterias (66hours)}{Bacterias(55hours)}=\frac{C*r^{\frac{66-t}{t}}}{C*r^{{\frac{55-t}{t}}}} \\\frac{384,384,000}{192,192,000} =r^{\frac{66-t}{t} -\frac{55-t}{t} } \\2 =r^{\frac{11}{t}}$

So with that r = 2 and each time interval correspond to 11 years

Then replacing in one you can get the initial amount of C

$Bacterias (55hours)=C*2^{\frac{55-11}{11} } 192,192,000 = C*32\\C= 6006000$

7 0

3 years ago

The school store marks up the price of all items by 30% before selling to

Readme [11.4K]

Answer:

$65.325 or $65.33

Step-by-step explanation:

When looking for a percentage in a number, you want to multiply that number by the percentage. Remember that all percentages are to the hundreth power, or 0.00. So if you want to find 30% of 50.25, you multiply it by 0.30 or 0.3. After calculating that you will come up with 15.075 as the percentage. Since the store is marking the price up, you add it to the original price. So your equation is 50.25 + 15.075 =?. After calculating that, you get the answer 65.325. That is only half of your answer though because, when dealing with money, you always round to the nearest hundredth. So when you round 65.325, you get 65.33 which should be the correct answer.

4 0

3 years ago