All categories

2 years ago

Need help with sigma notation

Mathematics

1 answer:

Solnce55 [7]2 years ago

7 0

Answer:

114126

Step-by-step explanation:

The given expression describes the GP with

The first term:

t = 80(1.23²⁻²) = 80(1.23⁰) = 80

The common ratio:

r = 1.23

It is required to find the sum of the terms from 2 (the bottom number of sigma) through 29 (the top number of sigma)

The number of terms is

n = 29 - 2 + 1 = 28

The sum of the first 28 terms is

Sₙ = t(rⁿ - 1)/(r - 1)
S₂₈ = 80(1.23²⁸ - 1)/(1.23 - 1) = 114125.75573 ≈ 114126 (rounded)

You might be interested in

ASAP PLEASE please please

Aleksandr [31]

${ \qquad\qquad\huge\underline{{\sf Answer}}}$

Let's solve ~

$\qquad \sf \dashrightarrow \: \cfrac{1}{b} + 10 = \cfrac{9}{b} + 7$

$\qquad \sf \dashrightarrow \: \cfrac{9}{b} - \cfrac{1}{b} = 10 - 7$

$\qquad \sf \dashrightarrow \: \cfrac{8}{b} = 3$

$\qquad \sf \dashrightarrow \: b = \cfrac{8}{3}$

5 0

2 years ago

Read 2 more answers

Can anyone pls help me in math<3

FinnZ [79.3K]

Answer:

Third number is 12

Step-by-step explanation:

Let $\displaystyle \large{d}$ be common difference & $\displaystyle \large{x}$ be the third number. Set up the following equations:

$\displaystyle \large{x-2d=-2 \to (1)}\\\\\displaystyle \large{x+2d=26 \to (2)}$

Solve the simultaneous equation for x-term:

$\displaystyle \large{2x=24}\\\\\displaystyle \large{x=12}$

Let’s make sure that we get accurately answer. Substitute x = 12 in any equations which I’ll choose (1):

$\displaystyle \large{12-2d=-2}\\\\\displaystyle \large{-2d=-14}\\\\\displaystyle \large{d=7}$

Now add each terms with common difference as 7:

-2+7 = 5

5+7 = 12

12+7 = 19

19+7 = 26

So our pattern is -2, 5, 12, 19, 26. Since the question only asks for third number then the answer is 12

8 0

2 years ago

Carla Eppelstein is saving her babysitting money to buy a bicycle. She usually babysits a total of 11 to 16 hours per week and c

mario62 [17]

Answer:

About three weeks.

Step-by-step explanation:

147 divided by 4.50 = 32.6

32.6 divided by 11 is almost 3. So about three weeks.

4 0

3 years ago

The number of digits in the square root of 49729 is

maw [93]

Answer:

Step-by-step explanation:

it's square root is 223.

it has 3 digits as 2 2 3..

3 is answer..

8 0

4 years ago

Evaluate (−25)(38)/(−34).

muminat

Multiply 25 and 38, the divide that by 34.
the negatives will cancel because there is 1 on the top and 1 on the bottom.
i got 27.9412

8 0

3 years ago