20 points and brainliest for one problem Pls give explination and answer>pls hurry:(

The distance traveled by a toy car can be modeled by D(t) = t3 − 3t2 + t − 3, where t > 3 represents time in seconds. If the

Bogdan [553]

Answer:

$t^2+1$

Step-by-step explanation:

We are given that

Distance traveled by a toy car

$D(t)=t^3-3t^2+t-3$

Where t>3

Time taken by car =t-3 seconds

We have to find the expression which represents the speed of the toy car.

We know that

$Speed=\frac{Distance}{time}$

Using the formula

$Speed=\frac{(t^3-3t^2+t-3)}{t-3}$

$Speed=\frac{t^2(t-3)+(t-3)}{t-3}$

$Speed=\frac{(t-3)(t^2+1)}{t-3}$

$Speed=t^2+1$

Hence, the expression which represents the speed of the toy car

$t^2+1$

5 0

3 years ago

Five bells begin to ring together and they ring at intervals of 3, 6, 10, 12 and 15 seconds, respectively. How many times will t

Evgen [1.6K]

Answer:

60 times will they ring together at the same second in one hour excluding the one at the end.

Step-by-step explanation:

Given : Five bells begin to ring together and they ring at intervals of 3, 6, 10, 12 and 15 seconds, respectively.

To find : How many times will they ring together at the same second in one hour excluding the one at the end?

Solution :

First we find the LCM of 3, 6, 10, 12 and 15.

2 | 3 6 10 12 15

2 | 3 3 5 6 15

3 | 3 3 5 3 15

5 | 1 1 5 1 5

| 1 1 1 1 1

$LCM(3, 6, 10, 12,15)=2\times 2\times 3\times 5$

$LCM(3, 6, 10, 12,15)=60$

So, the bells will ring together after every 60 seconds i.e. 1 minutes.

i.e. in 1 minute they rand together 1 time.

We know, 1 hour = 60 minutes

So, in 60 minute they rang together 60 times.

Therefore, 60 times will they ring together at the same second in one hour excluding the one at the end.

6 0

3 years ago

Olive buys indie music online. Each song costs $2 plus a $5 fee for using the artist's site. She has no more than $40 to spend.

SCORPION-xisa [38]

In constructing an inequality, you need to know the following:

1. What don't we know? How many songs can be bought? So, let x be the numbers of songs.
2. What do we know? Each songs costs $2 plus a fee for using the artist's site of $5.
3. Is there more than 1 possible solution? Yes, because there is enough money left if she only bought 1 song.

The meaning of no more than $40 means it must not exceed $40, $40 or less, or only $40.

So, song + fee can't be more than $40 and song + fee could equal to $40.

Therefore, song + fee for using an artist's site less than or equal to $40.
Final Answer: 2x+5 <= 40

7 0

4 years ago

Read 2 more answers

A man claims to have extrasensory perception (ESP). As a test, a fair coin is flipped 20 times, and the man is asked to predict

dlinn [17]

Answer:

$P(x\geq 17)=0.00128$

Step-by-step explanation:

The probability that the man gets x out of 20 correct follows a Binomial distribution, so the probability is calculated as:

$P(x)=\frac{n!}{x!(n-x)!}*p^{x}*(1-p)^{n-x}$

Where n is the number of identical experiments and p is the probability of success. In this case n is 20.

Additionally, if he has no ESP the probability that he predict correctly is 0.5, because he is only guessing.

Then, the probability that he gets x out of 20 correct is equal to:

$P(x)=\frac{20!}{x!(20-x)!}*0.5^{x}*(1-0.5)^{20-x}$

Therefore the probability that he would have done at least 17 out of 20 well if he had no ESP is:

$P(x\geq 17)=P(17)+P(18)+P(19)+P(20)\\$

Where:

$P(17)=\frac{20!}{17!(20-17)!}*0.5^{17}*(1-0.5)^{20-17}=0.00108719\\P(18)=\frac{20!}{18!(20-18)!}*0.5^{18}*(1-0.5)^{20-18}=0.00018119\\P(19)=\frac{20!}{19!(20-19)!}*0.5^{19}*(1-0.5)^{20-19}=0.00001907\\P(20)=\frac{20!}{20!(20-20)!}*0.5^{20}*(1-0.5)^{20-20}=0.00000095$

So, $P(x\geq 17)$ is equal to:

$P(x\geq 17)=0.00108719+0.00018119+0.00001907+0.00000095\\P(x\geq 17)=0.00128$

8 0

3 years ago

Find the circumference leave the answer in terms of pi

umka2103 [35]

The circumference is 56.18pi

8 0

3 years ago