All categories

2 years ago

An arrow is shot vertically upward at a rate of 280 feet per second. Use the projectile formula

Mathematics

1 answer:

vfiekz [6]2 years ago

4 0

Time is 16.75 seconds when the arrow reaches 200 ft

Step-by-step explanation:

Step 1: Find time at height of 200 ft

Height = 200 ft

v = 280 ft/s

Projectile formula, h = -16t² + vt

⇒ 200 = -16t² + 280t

⇒ 16t² - 280t + 200 = 0

⇒ 2t² - 35t + 25 = 0 (dividing by common factor 8)

Using quadratic formula to find t

t = (35 ±√35² - 4×2×25)/2×2

t = (35 ±√1225 - 200)4 = 35 ± 32.02/4

∴ t = 67/4 or 3/4

t = 16.75 seconds

You might be interested in

If the area of a triangle is 15 cm and the height is 6cm what is the base

adoni [48]

The base is 5 because the base = 2 Area/Height

6 0

2 years ago

Read 2 more answers

Consider the isosceles triangle below where the side lengths are given in cm:

DiKsa [7]

Answer:

I think is B

because its the one that sounds good

7 0

2 years ago

Which of the following expressions has 3 terms?<br><br> A 8x + y - z<br> B xyz<br> C y3 + 1

Alja [10]

Since C only has two and although it may look like B has three terms, when the letters are joined together like that they are basically just become one big term, so your answer would be A.

5 0

3 years ago

Read 2 more answers

A jury pool has 18 people that are married and 22 people that are not married, from which 12 jurors will be selected. Assuming t

ivolga24 [154]

If the pool has 18 married and 22 not married, this means there are 40 people total
this means there’s a 18/40 probability that people who are married will be chosen
18/40 = 2/5
There is a 22/40 probability people who are un married will be chosen
22/40 = 11/20

3 0

3 years ago

Find the probability of at least 6 failures in 7 trials of a binomial experiment in which the probability of success in any one

oksano4ka [1.4K]

Answer:

$P(x \geq 6)=P(X=6)+P(X=7)$

And we can find the individual probabilities:

$P(X=6)=(7C6)(0.91)^6 (1-0.91)^{7-6}=0.358$

$P(X=7)=(7C7)(0.91)^7 (1-0.91)^{7-7}=0.517$

And replacing we got:

$P(x \geq 6)=P(X=6)+P(X=7)= 0.358+0.517=0.875$

Step-by-step explanation:

Previous concepts

The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".

Solution to the problem

Let X the random variable of interest, on this case we now that:

$X \sim Binom(n=7, p=1-0.09=0.91)$

The probability associated to a failure would be p =1-0.09 = 0.91

The probability mass function for the Binomial distribution is given as:

$P(X)=(nCx)(p)^x (1-p)^{n-x}$

Where (nCx) means combinatory and it's given by this formula:

$nCx=\frac{n!}{(n-x)! x!}$

And we want to find this probability:

$P(x \geq 6)=P(X=6)+P(X=7)$

And we can find the individual probabilities:

$P(X=6)=(7C6)(0.91)^6 (1-0.91)^{7-6}=0.358$

$P(X=7)=(7C7)(0.91)^7 (1-0.91)^{7-7}=0.517$

And replacing we got:

$P(x \geq 6)=P(X=6)+P(X=7)= 0.358+0.517=0.875$

6 0

2 years ago