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3 years ago

9

What number is 3 more then 20% of 40%?

2 answers:

Kamila [148]3 years ago

7 0

Answer:

8

Step-by-step explanation:

Elina [12.6K]3 years ago

7 0

Answer:

11

Step-by-step explanation:

20% of 40 is just 40/5, which equals 8. 8+3=11.

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Create a real life example using either temperature or money to compare -3 and -5

lana66690 [7]

The temperature when I went to the bus stop in the morning felt like it was -3°, sadly it was only -5° only two degrees warmer, which means it is still freezing

7 0

3 years ago

Read 2 more answers

How many pounds of a 15% copper alloy must be mixed with 700lb of a 30% copper alloy to maybe a 25.5% copper alloy

lisov135 [29]

Answer:

$300\; \rm lb$ .

Step-by-step explanation:

Let $x$ represent the mass (in pounds) of that $15\%$ copper alloy required, such that the final mixture would contain $25.5\%$ copper by mass.

Consider: if $x$ pounds of that $15\%$ copper alloy is mixed with $700$ pounds that $30\%$ copper alloy, what would be the mass of copper in the mixture?

Mass of copper in $x$ pounds of that $15\%$ copper alloy: $(0.15\, x)\; \rm lb$ .
Mass of copper in $700$ pounds of that $30\%$ copper alloy: $700 \times 0.30 = 210\; \rm lb$ .

Therefore, the mixture would contain $(210 + 0.15\, x) \; \rm lb$ of copper.

The mass of that mixture would be $(700 + x)\; \rm lb$ . The mass fraction of copper in that mixture would be:

$\displaystyle \frac{(210 + 0.15\, x)\; \rm lb}{(700 + x)\; \rm lb} \times 100\%$ .

This ratio is supposed to be equal to $25.5\%$ . These two pieces of equations combine to give an equation about $x$ :

$\displaystyle \frac{(210 + 0.15\, x)\; \rm lb}{(700 + x)\; \rm lb} \times 100\% = 25.5\%$ .

$\displaystyle \frac{210 + 0.15\, x}{700 + x} = 0.255$ .

Simplify and solve for $x$ :

$210 + 0.15\, x= 0.255\, (700 + x)$ .

$(0.255 - 0.15)\, x= 210 - 0.255 \times 700$ .

$\displaystyle x = \frac{210 - 0.255 \times 700}{0.255 - 0.15} = 300$ .

Therefore, $300\; \rm lb$ of that $15\%$ alloy would be required.

4 0

3 years ago

slavikrds [6]

Answer:

The first number lets say is x

the second is y so

y=1/2x+8

x+1/2x+8=58

1 1/2x=50

x= 33 1/3

Hope This Helps!!!

6 0

3 years ago

Read 2 more answers

Evaluate f(1) = 3x + 8

Oksi-84 [34.3K]

Answer:

11

Step-by-step explanation:

f(1) = 3(1) + 8 = 3 + 8 = 11

8 0

3 years ago

Read 2 more answers

If f(x)=1−x^2 +x^3 , then f(−1)=

Andrews [41]

Answer:

f(-1) = -1

General Formulas and Concepts:

<u>Pre-Algebra</u>

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right<u> </u>

<u>Algebra I</u>

Functions
Function Notation

Step-by-step explanation:

<u>Step 1: Define</u>

<em>Identify</em>

f(x) = 1 - x² + x³

f(-1) is <em>x</em> = -1 for the function f(x)

<u>Step 2: Evaluate</u>

Substitute in <em>x</em> [Function f(x)]: f(-1) = 1 - (-1)² + (-1)³
Exponents: f(-1) = 1 - 1 - 1
Subtract: f(-1) = -1

6 0

3 years ago