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3 years ago

For the series 16, 24, 36, 54... find s7

Mathematics

1 answer:

Masja [62]3 years ago

4 0

Answer:

C.) 514.75

Step-by-step explanation:

r = 24/16 = 1.5

r = 36/24 = 1.5

r = 54/36 = 1.5

16 + 24 + 36 + 54 + 81 + 121.5 + 182.25 = 514.75

or use:

Sn = a[ (1-r^n) / (1 - r) ]

S7 = 16[ (1 - 1.5^7) / (1 - 1.5) ]

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What is the sum of all possible values of y if x is a positive integer, xy > 0, and 6x+2y=25?

SIZIF [17.4K]

Option E

The sum of all possible values of y is 20

Solution:

Given that,

6x + 2y = 25

Where, xy > 0

We have to find the sum of all possible values of y if x is a positive integer

We can use values of x = 1, 2, 3, 4

For x = 5 and above, y will be negative

Substitute x = 1 in given equation

6(1) + 2y = 25

6 + 2y = 25

2y = 25 - 6

2y = 19

Divide both the sides of equation by 2

$y = \frac{19}{2}$

Substitute x = 2 in given equation

6(2) + 2y = 25

2y = 25 - 12

2y = 13

Divide both the sides of equation by 2

$y = \frac{13}{2}$

Substitute x = 3 in given equation

6(3) + 2y = 25

2y = 25 - 18

2y = 7

Divide both the sides of equation by 2

$y = \frac{7}{2}$

Substitute x = 4 in given equation

6(4) + 2y = 25

24 + 2y = 25

2y = 25 - 24

2y = 1

Divide both the sides of equation by 2

$y = \frac{1}{2}$

Now add all the values of "y"

$\text{Sum of possible values of y } = \frac{19}{2} + \frac{13}{2} + \frac{7}{2} + \frac{1}{2}\\\\\text{Sum of possible values of y } = \frac{19+13+7+1}{2}\\\\\text{Sum of possible values of y } = \frac{40}{2}=20$

Thus sum of all possible values of y is 20

3 0

3 years ago

Charlie weighs 9 pounds more than his little brother. If together they weigh 99 pounds what is the algebraic equation for Charli

Afina-wow [57]

To set up the equation you would take x and add the nine pounds that Charlie weighs more than his brother and the set that equal to 99. Your equation would be X+9=99. If you wanted to take it a step further and solve the equation you would distract 9 from both sides which means that x=90

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4 years ago

Solve the following equation for x, in terms of a and b ax= 15+bx

ZanzabumX [31]

Ax=15+bx
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3 years ago

The radius of the base of a right circular cone is 7 times greater than the radius of another right circular cone. If the height

Simora [160]

Answer: option D is the correct answer.

Step-by-step explanation:

Let the height of both cones be h

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Volume of the smaller cone is

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Volume of the larger cone is

1/3(π ×(7r)²h)

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the volume of the larger cone divided by the volume of the smaller cone is

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