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3 years ago

An element with mass 290 grams decays by 13.2% per minute. How much of the

Mathematics

2 answers:

snow_lady [41]3 years ago

8 0

Answer:

40.0 grams

Step-by-step explanation:

An exponential decay function is

$y=a(1-r)^t$ .... (1)

where, a is initial value, t is time and r is decay rate.

It is given that element with mass 290 grams decays by 13.2% per minute.

Initial value = 290

Decay rate = 13.2% = 0.132

Substitute a=290 and r=0.132 in equation (1).

$y=290(1-0.132)^t$

$y=290(0.868)^t$

Substitute t=14 to find the amount of element remaining after 14 minutes.

$y=290(0.868)^{14}$

$y=39.9644785$

Round the solution to the nearest tenth.

$y\approx 40.0$

Therefore, element with mass 40.0 grams is remaining after 14 minutes.

Tatiana [17]3 years ago

4 0

Answer:

FV=PV(1−d)^n

FV = 290(1-.132)^14

FV = 290(.868)^14

FV = 39.96 g

Step-by-step explanation:

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Identify the equation of the parabola in vertex form if a = 1 and the vertex is (4, 6).

Y_Kistochka [10]

Answer:

Step-by-step explanation:

8 0

2 years ago

Fill in the missing numbers to create equivalent ratios.

jasenka [17]

Step-by-step explanation:

The way to find missing numbers in equivalent ratios is to multiply the means (the first denominator and the second numerator) and multiply the extremes (the first numerator and the second denominator). It sounds really complicated, but it is quite simple =)

2/5 = x/10

The means in this equivalent ration are 5 and x. The extremes are 2 and 10.

5x = 20

Now solve =)

x = 4

That was pretty simple. Let's move on to the next one. Do exactly the same thing here:

4/10 = 6/x

60 = 4x

15 = x

That was pretty simple, too! Keep going!

6/15 = x/25

15x = 150

x = 10

All of these should be equal, so check them by dividing:

2/5 = 0.4

4/10 = 0.4

6/15 = 0.4

10/25 = 0.4

They all check out, so these are your answers: 2/5, 4/10, 6/15, 10/25

I really hope this helps you =)

8 0

3 years ago

Read 2 more answers

A website manager has noticed that during the evening hours, about 5 people per minute check out from their shopping cart and m

Over [174]

Answer:

a) Poisson distribution

b) 99.33% probability that in any one minute at least one purchase is made

c) 0.05% probability that seven people make a purchase in the next four minutes

Step-by-step explanation:

In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

$P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}$

In which

x is the number of sucesses

e = 2.71828 is the Euler number

$\mu$ is the mean in the given time interval.

5 people per minute check out from their shopping cart and make an online purchase.

This means that $\mu = 5$

a) What model might you suggest to model the number of purchases per minute? 

The only information that we have is the mean number of an event(purchases) in a time interval. Each event is also independent fro each other. So you should suggest the Poisson distribution to model the number of purchases per minute.

b) What is the probability that in any one minute at least one purchase is made? 

Either no purchases are made, or at least one is. The sum of the probabilities of these events is 1. So

$P(X = 0) + P(X \geq 1) = 1$