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3 years ago

Percents

Mathematics

1 answer:

pentagon [3]3 years ago

5 0

Answer:

$10.17
$70.57

Step-by-step explanation:

1. The change in value was 12.6% of $80.74, calculated as ...

0.126×$80.74 = $10.17324 ≈ $10.17

2. The new price is lower than the price yesterday by that amount, so is ...

$80.74 -10.17 = $70.57

_____

Note on percents

A percent should be no mystery. The word "per cent" literally means "per hundred", or "/100" in symbols. The symbol "%" is a shorthand way to write "/100". So 12.6% means 12.6/100 = 126/1000 = 0.126.

When written as a decimal, the units digit of a percent is placed in the hundredths digit of the decimal number, as you can see in the example above. (The "2" in "12.6" is in the hundredths place in 0.126.)

Generally percentages are used to express ratios. They are usually a "pure number" with no units attached. Since they are a ratio, they are generally useless unless you know what the numbers involved in the ratio are. Here, the denominator of the ratio, the "base" or "reference", is yesterday's stock price. The percentage is described as the drop in price since yesterday, so it is the ratio ...

(drop in price since yesterday)/(yesterday's price)

Both of these values have units of dollars, so the numerator units cancel the denominator units and what is left is a pure number. The ratio is 0.126, so to express it as a percentage, we multiply it by 100%. Of course, 100% = 100/100 = 1, so we haven't changed the value; we've only changed the way it is presented. That is ...

0.126 = 0.126 × 100% = 12.6%

_____

Additional note on decimals and percents

You may hear that to convert a decimal to a percent, you multiply it by 100. That is only partly right. Multiplying anything by 100 changes its value by that factor. When you change a decimal to a percentage, the goal is not to change the value, merely the form. What you actually want to do is multiply by 100% = 100/100. In the example we're using here, this looks like ...

0.126 × 100/100 = 12.6/100 = 12.6% . . . . . . remember that % means /100.

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geniusboy [140]

$f(x)=\frac{(x+3)(x-2)(x+5)}{(x-3)(x+2)(x-5)}$

Bobby is right, because at x = -2, 3, and 5, the denominator of the function equals zero, which is by definition undefined.

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use the data set shown below to complete the sentence. 3, 3, 4, 5, 5, 9 the mean is ___________ the median. 1.less then 2.equal

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3. Greater than

Median is the middle number of the data set. But in this senario, there are 2 numbers in the middle. So you can take 4+5/2=4.5

To find Mean, you can must take all the numbers in the data set divided by the number of data collected.

In this case, (3+3+4+5+5+9)÷6

You will find that the mean is greater than the median.

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4 years ago

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Find two integers whose sum 2and product is _3

Marat540 [252]

Answer:

The two integers should be 3 and 1

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2 years ago

Esteban has a big jar of change in his room. He has 600 coins total, and 240 of them are pennies. What percentage of the coins a

Thepotemich [5.8K]

<h2>40 % of coins are pennies.</h2>

Step-by-step explanation:

Total number of coins = 600

Total number of pennies = 240

$\texttt{Percentage of the coins are pennies=}\frac{\texttt{Total number of pennies}}{\texttt{Total number of coins}}\times 100\\\\\texttt{Percentage of the coins are pennies=}\frac{240}{600}\times 100\\\\\texttt{Percentage of the coins are pennies=}\frac{240}{6}\\\\\texttt{Percentage of the coins are pennies=}\frac{120}{3}\\\\\texttt{Percentage of the coins are pennies=}40\%$

40 % of coins are pennies.

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4 years ago

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There is a rectangular lot in the garden, with 7 ft in length and 5 ft in width. You plan to expand the lot by an equal length a

zubka84 [21]

Answer:

3 ft at each end

Step-by-step explanation:

The lot area is 7 x 5 = 35ft2

The planned lot area = 143ft2

The plan is to extend the lot by equal length on both the width and the length therefore we can express the extension as y the planned lot can be express as

(5+y) x (7+y) = 143

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(y-6) =0 or (y +18)= 0

y =6. or y = -18

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6/2 = 3 ft at each end

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3 years ago