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3 years ago

Make a conjecture about the sum of the first 15 positive even number

1 answer:

6 0

I conclude that the sum will be even because any even number can be represented by 2n where n is a whole number
and even numbers are 2 apart, so
the sum of the first 15 are
2n+2(n+1)+2(n+2) etc until we get to 2(n+14)
we can undistribute the 2 from all of them and get
2(n+n+1+n+2...n+14)
and we are sure that whatever is in the parenthasees is a whole number because whole+whole=whole
therefor, the sum is even

if you did want to find the sum then
an=2n
the 15th even number is 30
the first is 2
S15=15(2+30)/2=15(32)/2=15(16)=240
which is even

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Calculate the value of (6.72 10^5)+ (3.2 x 10^4) Give your answer in standard form.

dangina [55]

Answer:

$7.04\cdot 10^{5}$ or 704,000

Step-by-step explanation:

Standard Form of Numbers

Any number that we can write as a decimal number between 1.0 and 10.0, multiplied by a power of 10, is said to be in Scientific Notation. Some authors consider standard form and scientific form as the same, but others state that standard form is the common form of expressing numbers, i.e., a sequence of digits, separated by thousands by a comma, and separated from the decimal part by a dot.

We'll give here both answers.

We have to calculate:

$6.72\cdot 10^{5}+3.2\cdot 10^{4}$

Since the numbers don't have the same exponent, we must make them equal. Let's make the second number have an exponent of 5, by dividing by 10:

$6.72\cdot 10^{5}+3.2\cdot 10^{4}=6.72\cdot 10^{5}+3.2/10\cdot 10^{5}$

$6.72\cdot 10^{5}+3.2\cdot 10^{4}=6.72\cdot 10^{5}+0.32\cdot 10^{5}$

Now we add:

$6.72\cdot 10^{5}+3.2\cdot 10^{4}=7.04\cdot 10^{5}$

It's correctly expressed in scientific notation. Now to convert to 'standard form', multiply by $10^5=100,000$ :

$6.72\cdot 10^{5}+3.2\cdot 10^{4}=7.04*100,000=704,000$

7 0

3 years ago

Solve: 3 + √x+2 = 11 62 64 ()

klemol [59]

Answer: its 62

Step-by-step explanation:

Isolate the radical, then raise each side of the equation to the power of its index.

3 0

3 years ago

Andy wants to buy a refrigerator for $769, a stove for $359, and a dishwasher for $309. round each cost to the nearest hundred t

Fiesta28 [93]

769 rounded to nearest 100 = 800

359 rounded to nearest 100 = 400

309 rounded to nearest 100 = 300

800 + 400 + 300 = $1,500 estimated total cost

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2 years ago

Which of the following is not an integer? Group of answer choices -1 -2.5 4 25Which of the following is not an integer?

Paha777 [63]

The correct answer is -2.5

6 0

2 years ago

Read 2 more answers

If a person uses $700 in credit with an interest of 14%,what is that person going to owe after three billing cycles with simple

Brums [2.3K]

Simple interest: i = p*r*t, where r is the annual interest rate and t is the number of years.
14%
This boils down to ----------- interest per month: a monthly rate of 0.0117.
12 mo

Thus, after 3 months, the amount owed, including the original $700, would be $700 + 3($700)(0.0117) = $724.57.

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2 years ago