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Sonja [21]
1 year ago
12

the rule for being the nth item in a certain sequence is n(n+1)/2. what is the 4th term in this sequence ? a.) 4b.)10c.)16d.)20

Mathematics
1 answer:
abruzzese [7]1 year ago
3 0

The 4th term of the sequence can be determined as,

\begin{gathered} a_n=\frac{n(n+1)}{2} \\ a_4=\frac{4(4+1)}{2} \\ a_4=10 \end{gathered}

Thus, option (b) is correct.

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How do you add and subtract decimals as easily as you do whole numbers?
777dan777 [17]

If you know how to add and subtract whole numbers, then you can add and subtract decimals! Just be sure to line up the terms so that all the decimal points are in a vertical line.
To add decimal numbers:

Put the numbers in a vertical column, aligning the decimal points
Add each column of digits, starting on the right and working left. If the sum of a column is more than ten, "carry" digits to the next column on the left.
Place the decimal point in the answer directly below the decimal points in the terms.
To subtract decimal numbers:

Put the numbers in a vertical column, aligning the decimal points.
Subtract each column, starting on the right and working left. If the digit being subtracted in a column is larger than the digit above it, "borrow" a digit from the next column to the left.
Place the decimal point in the answer directly below the decimal points in the terms.
Check your answer by adding the result to the number subtracted. The sum should equal the first number.

To add these numbers, first arrange the terms vertically, aligning the decimal points in each term. Don't forget, for a whole number like the first term, the decimal point lies just to the right of the ones column. You can add zeroes to the right of the decimal point to make it easier to align the columns. Then add the columns working from the right to the left, positioning the decimal point in the answer directly under the decimal points in.

To subtract these numbers, first arrange the terms vertically, aligning the decimal points in each term. You can add zeroes to the right of the decimal point, to make it easier to align the columns. Then subtract the columns working from the right to the left, putting the decimal point in the answer directly underneath the decimal points in the terms. Check your answer by adding it to the second term and making sure it equals the first.










· Place value

· Decimal numbers

· Estimating and
rounding

· Adding / subtracting
decimals

· Multiplying decimals

· Dividing decimals

· Percent

· Exponents

· Square roots

· Signed integers

· Adding and
subtracting integers

· Multiplying and
dividing integers

· Properties of integers








First Glance In Depth Examples Workout
First Glance In Depth Examples Workout

Adding and subtracting decimals
4 0
3 years ago
Read 2 more answers
Able, Ben and Cal each played a game able's score was six times ben's score, Cale score was a hird time of Able's score write do
Svetradugi [14.3K]

Answer:

Abel to Ben: 6

Abel to Carl: 3

Ben to Carl: 0.5

Step-by-step explanation:

First we formulate the problem in equations:

Abel = 6 * Ben

Cale = Abel / 3

If Cale's score is Abel's score over 3, so Abel's score is 3 times Cale's score.

If Abel's score is 6 times Ben's score, and 3 times Cale's score, then Cale's score is 2 times Ben's score (so Ben's score is 0.5 times Cale's score)

So, the ratio between all scores are the following:

Abel to Ben: 6

Abel to Carl: 3

Ben to Carl: 0.5

8 0
3 years ago
Read 2 more answers
Solve:<br> 2x - 20<br> 3<br> - 2x (5 points)<br> a<br> -5 -3<br> a<br> 13
kow [346]

Answer:

Negative five and negative three

6 0
3 years ago
Not sure how to find what x equals
Llana [10]

Answer:

Its 48 °

Since its a triangle, the total angle will be 180°

So,

x° + 42°+90°=180°(90° as one angle in triangle is 90°)

x°=180°-90°-42°

x°=48°

7 0
2 years ago
Read 2 more answers
Y = f(x) = 2^x
Virty [35]

Answer:

The value of f(x) when x=-1 is 0.5

Therefore f(-1)=0.5

Step-by-step explanation:

Given that y=f(x)=2^x

to find the f(x) when x=-1 :

That is to find f(-1)

Put x=-1 in the given function f(x)=2^x

f(-1)=2^{-1}

=\frac{1}{2}

=0.5

Therefore f(-1)=0.5

The value of f(x) when x=-1 is 0.5

3 0
3 years ago
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