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3 years ago

Simplify the expression. -1 -5.7| A. 6 B. -6 C. -5.7 D. 5.7

Mathematics

1 answer:

stepan [7]3 years ago

7 0

Answer:

none of those answers, it should be -6.7

Step-by-step explanation:

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What vaulue of K anwsers the qestion.....K -4 = 1/256 please hurry its the last one i cant fail :(

iogann1982 [59]

K=4+1/256

If this is a multiple choice question, please provide the choices ;)

4 0

3 years ago

The sequence$$1,2,1,2,2,1,2,2,2,1,2,2,2,2,1,2,2,2,2,2,1,2,\dots$$consists of $1$'s separated by blocks of $2$'s with $n$ $2$'s i

kicyunya [14]

Consider the lengths of consecutive 1-2 blocks.

block 1 - 1, 2 - length 2

block 2 - 1, 2, 2 - length 3

block 3 - 1, 2, 2, 2 - length 4

block 4 - 1, 2, 2, 2, 2 - length 5

and so on.

Recall the formula for the sum of consecutive positive integers,

$\displaystyle \sum_{i=1}^j i = 1 + 2 + 3 + \cdots + j = \frac{j(j+1)}2 \implies \sum_{i=2}^j = \frac{j(j+1) - 2}2$

Now,

$1234 = \dfrac{j(j+1)-2}2 \implies 2470 = j(j+1) \implies j\approx49.2016$

which means that the 1234th term in the sequence occurs somewhere about 1/5 of the way through the 49th 1-2 block.

In the first 48 blocks, the sequence contains 48 copies of 1 and 1 + 2 + 3 + ... + 47 copies of 2, hence they make up a total of

$\displaystyle \sum_{i=1}^48 1 + \sum_{i=1}^{48} i = 48+\frac{48(48+1)}2 = 1224$

numbers, and their sum is

$\displaystyle \sum_{i=1}^{48} 1 + \sum_{i=1}^{48} 2i = 48 + 48(48+1) = 48\times50 = 2400$

This leaves us with the contribution of the first 10 terms in the 49th block, which consist of one 1 and nine 2s with a sum of $1+9\times2=19$ .

So, the sum of the first 1234 terms in the sequence is 2419.

8 0

2 years ago

A price is decreased from £800 to £640. Calculate the percentage change.

Anni [7]

<span>There is a decrease of 20% from ÂŁ800 to ÂŁ640.

A change from 800 to 640 represents a negative change (decrease) of -20% Using the formula :

Percent change = [(800 - 640) / 800] x 100 = -20 % (decrease)

800 is the old value and 640 is the new value. In this case we have a negative change (decrease) of -20 percent because the new value is smaller than the old value.</span>

6 0

3 years ago

Read 2 more answers

Please help me asap! please show your work

solmaris [256]

Make a proportion
81/30 = x/600
600/30 = 20
x/81 = 20
x = 1620
Solution: 1620 calories

7 0

3 years ago

A university class has 26 students: 12 are art majors, 9 are history majors, 5 and are nursing majors. The professor is planning

azamat

Answer:

6.9%.

Step-by-step explanation:

Given that a university class has 26 students: 12 are art majors, 9 are history majors, 5 and are nursing majors, and the professor is planning to select two of the students for a demonstration, where the first student will be selected at random, and then the second student will be selected at random from the remaining students, to determine what is the probability that the first student selected is a history major and the second student is a nursing major the following calculations must be performed:

26 = 100

9 = X

9 x 100/26 = X

900/26 = X

34.61 = X

25 = 100

5 = X

500/25 = X

20 = X

0.2 x 0.3461 = X

0.069 = X

Thus, the probability that the first student selected is a history major and the second student is a nursing major is 6.9%.

8 0

3 years ago

Read 2 more answers