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3 years ago

8

If a certain negative number is multiplied by six, the result is the same as 20 less than the original number. What is the value

of the original number?

1 answer:

Wittaler [7]3 years ago

5 0

let the number be X
6X=X-20
X+6X=20
-5X=20
X=-4

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What is the missing length??

amid [387]

Answer

The missing length is 10

Step-by-step explanation:

Represent the missing length with x

The sides of the given shape are directly proportional.

Mathematically:

(15 + x) to (12 + 8) and x to 7

Represent as a ratio:

$(15 + x) : (12 + 8) = x : 8$

$15 + x : 20= x : 8$

Convert to fraction

$\frac{15 + x}{20} = \frac{x}{8}$

Cross Multiply:

$(15 + x)*8 = 20 * x$

$120 + 8x = 20x$

Collect Like Terms

$20x - 8x = 120$

$12x = 120$

Solve for x

$x = \frac{120}{10}$

$x = 10$

<em>The length of the missing side is 10</em>

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Kevin weighed his baggage before going on a trip. In what unit did the measuring scale show the weight of his baggage? What is t

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Step-by-step explanation:

the answer is lbs i think

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The head of the Westlane Cultural Center wants to get a sense of how quickly pledges from donors arrive at the center. It takes

Rzqust [24]

Answer:

95.64% probability that pledges are received within 40 days

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

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This is the pvalue of Z when X = 40. So

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3 years ago

Consider a tank used in certain hydrodynamic experiments. After one experiment the tank contains liters of a dye solution with a

Alja [10]

Answer:

t = 460.52 min

Step-by-step explanation:

Here is the complete question

Consider a tank used in certain hydrodynamic experiments. After one experiment the tank contains 200 liters of a dye solution with a concentration of 1 g/liter. To prepare for the next experiment, the tank is to be rinsed with fresh water flowing in at a rate of 2 liters/min, the well-stirred solution flowing out at the same rate.Find the time that will elapse before the concentration of dye in the tank reaches 1% of its original value.

Solution

Let Q(t) represent the amount of dye at any time t. Q' represent the net rate of change of amount of dye in the tank. Q' = inflow - outflow.

inflow = 0 (since the incoming water contains no dye)

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㏑Q = -t/100 + c

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when t = 0, Q = 200 L × 1 g/L = 200 g

$Q(0) = 200 = Ae^{(-0/100)} = Ae^{(0)} = A\\A = 200.\\So, Q(t) = 200e^{(-t/100)}$

We are to find t when Q = 1% of its original value. 1% of 200 g = 0.01 × 200 = 2

$2 = 200e^{(-t/100)}\\\frac{2}{200} = e^{(-t/100)}$

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t = -100㏑0.01

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