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3 years ago

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Which statement is true?

1 answer:

g100num [7]3 years ago

6 0

A is the answer to the equation

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Ppppplease help me asap!!! 15 points!!!!!

Furkat [3]

Imagine a ladder leaning against the wall and you know the height of the ladder and its distance from the wall and you had to find out the height you could use pythagorean theorem here

7 0

3 years ago

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A fan is marked up 40% on the original price. The original price was $20. What is the new price of the fan before sales tax?

Andre45 [30]

Answer:

$28

Step-by-step explanation:

The markup was 0.40×$20 = $8, so the new price is ...

$20 +8 = $28

7 0

3 years ago

The bill for Dino's lunch was $19.45. He wanted to leave 20% of the total bill as a tip. How much should the tip be?

Salsk061 [2.6K]

You could multiply 19.45 by 0.2 to solve for it, but if you're not using a calculator, then 19.45/5 would be much more convenient and easier.

0.2 is 1/5 in fraction form, which is why we can do that.

19.45/5 = 3.89

Dino should leave $3.89 as a tip.

7 0

3 years ago

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Oil is pumped continuously from a well at a rate proportional to the amount of oil left in the well. Initially there were millio

JulijaS [17]

Answer:

The amount of oil was decreasing at 69300 barrels, yearly

Step-by-step explanation:

Given

$Initial =1\ million$

$6\ years\ later = 500,000$

Required

At what rate did oil decrease when 600000 barrels remain

To do this, we make use of the following notations

t = Time

A = Amount left in the well

So:

$\frac{dA}{dt} = kA$

Where k represents the constant of proportionality

$\frac{dA}{dt} = kA$

Multiply both sides by dt/A

$\frac{dA}{dt} * \frac{dt}{A} = kA * \frac{dt}{A}$

$\frac{dA}{A} = k\ dt$

Integrate both sides

$\int\ {\frac{dA}{A} = \int\ {k\ dt}$

$ln\ A = kt + lnC$

Make A, the subject

$A = Ce^{kt}$

$t = 0\ when\ A =1\ million$ i.e. At initial

So, we have:

$A = Ce^{kt}$

$1000000 = Ce^{k*0}$

$1000000 = Ce^{0}$

$1000000 = C*1$

$1000000 = C$

$C =1000000$

Substitute $C =1000000$ in $A = Ce^{kt}$

$A = 1000000e^{kt}$

To solve for k;

$6\ years\ later = 500,000$

i.e.

$t = 6\ A = 500000$

So:

$500000= 1000000e^{k*6}$

Divide both sides by 1000000

$0.5= e^{k*6}$

Take natural logarithm (ln) of both sides

$ln(0.5) = ln(e^{k*6})$

$ln(0.5) = k*6$

Solve for k

$k = \frac{ln(0.5)}{6}$

$k = \frac{-0.693}{6}$

$k = -0.1155$

Recall that:

$\frac{dA}{dt} = kA$

Where

$\frac{dA}{dt}$ = Rate

So, when

$A = 600000$

The rate is:

$\frac{dA}{dt} = -0.1155 * 600000$

$\frac{dA}{dt} = -69300$

<em>Hence, the amount of oil was decreasing at 69300 barrels, yearly</em>

7 0

2 years ago

What is volume and how is it measured?

USPshnik [31]

Volume is the amount of space that a substance or object occupies, or that is enclosed within a container. It is measured in <span>Volumetric units. </span>

6 0

3 years ago

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