Which of the following is a composite number? 61 , 13 , 63 , 31

Find the sum of the first 7 terms of the following series, to the nearest integer.

Virty [35]

Answer:

$r = 2.5 \\ sum = \frac{a( {r}^{n - 1} )}{r - 1} \\ = \frac{125( {2.5}^{7 - 1} )}{7 - 1} \\ = \frac{30517.6}{6} \\ = 5086.3$

5 0

3 years ago

PLEASE HELP ME!

algol13

Step-by-step explanation:

$1.\sum_{i=1}^{5}3i$

The simplest method is "brute force". Calculate each term and add them up.

∑ = 3(1) + 3(2) + 3(3) + 3(4) + 3(5)

∑ = 3 + 6 + 9 + 12 + 15

∑ = 45

$2.\sum_{k=1}^{4}(2k)^{2}$

∑ = (2×1)² + (2×2)² + (2×3)² + (2×4)²

∑ = 4 + 16 + 36 + 64

∑ = 120

$3.\sum_{k=3}^{6}(2k-10)$

∑ = (2×3−10) + (2×4−10) + (2×5−10) + (2×6−10)

∑ = -4 + -2 + 0 + 2

∑ = -4

4. 1 + 1/4 + 1/16 + 1/64 + 1/256

This is a geometric sequence where the first term is 1 and the common ratio is 1/4. The nth term is:

a = 1 (1/4)ⁿ⁻¹

So the series is:

$\sum_{j=1}^{7}(\frac{1}{4})^{j-1}$

5. -5 + -1 + 3 + 7 + 11

This is an arithmetic sequence where the first term is -5 and the common difference is 4. The nth term is:

a = -5 + 4(n−1)

a = -5 + 4n − 4

a = 4n − 9

So the series is:

$\sum_{j=1}^{5}(4j-9)$

5 0

3 years ago

Plz help. jus wanna answer :)

skad [1K]

Answer:

The measure of uT is given = 31.6

and it is given ,that WV bisect the line UT

so,the measurement of US = 31.6/2

 = 15.8 

hope it helps and your day will be full of happiness

8 0

3 years ago

Which of these is an example of typing at an average rate of 42 words per minute?

Fudgin [204]

Answer:

I think that it is typing 16 words in 3/2 of a minute.

Step-by-step explanation:

16 times 3 = 48

Im sorry if you get this wrong, i tried my best.

6 0

3 years ago

Read 2 more answers

Solve for X, 132 is an exterior angle. Show work please!

Darina [25.2K]

Answer:

105/9

Step-by-step explanation:

180 - 132 = 48 degrees

180 - 48 - 45

= 180 - 93

= 87 degrees

<2 = 180 - 87

= 93 degrees

=> 9x - 12 = 93

=> 9x = 105

=> x = 105/9

6 0

2 years ago

Read 2 more answers