Who invented the no zero

The function y= -16t^2 +24t represents the height y (in feet) of a tennis ball bouncing straight up from the ground t seconds af

taurus [48]

We want to know the time, t, it takes the ball to reach a height (y) of 0.
$0=-16t^2+24t$
We can factor out the GCF first. The largest number that will divide evenly into 16 and 24 is 8. Also, both terms have a t, so we can factor that out as well:
$0=8t(-2t+3)$ (-16/8 = -2 and 24/8 = 3)
Using the zero product property, we know that either 8t=0 or -2t+3=0. Solving the first equation, we would divide both sides by 8:
8t/8=0/8
t=0
This is at 0 seconds, before the ball is in the air at all.
Solving the second equation, we start by subtracting 3 from both sides:
-2t+3-3=0-3
-2t=-3
Now we divide both sides by -2
-2t/-2=-3/-2
t=1.5
After 1.5 seconds, the ball will hit the ground again.

5 0

3 years ago

(12 points and brainliest!) A group of armed forces personnel were surveyed. The branch of service was recorded in the chart bel

Rzqust [24]

Answer:

43.2 degrees

Step-by-step explanation:

1. First, find the total number of people who were surveyed.

165+135+60+130+10=500

2. Next, figure out how many the Marine Corps is out of those 500 people.

60/500= 0.12 =12%

3. Last, find out what degree the 12% would take up.

We know that a circle is 360 degrees. To find 12% of 360 degrees, you will do:

0.12*360=43.2

So, the answer is 43.2 degrees

5 0

3 years ago

A local car dealer claims that 25% of all cars in San Francisco are blue. You take a random sample of 600 cars in San Francisco

sammy [17]

Answer:

No, we can't reject the dealer's claim with a significance level of 0.05.

Step-by-step explanation:

We are given that a local car dealer claims that 25% of all cars in San Francisco are blue.

You take a random sample of 600 cars in San Francisco and find that 141 are blue.

Let p = proportion of all cars in San Francisco who are blue

SO, Null Hypothesis, $H_0$ : p = 25% {means that 25% of all cars in San Francisco are blue}

Alternate Hypothesis, $H_A$ : p $\neq$ 25% {means that % of all cars in San Francisco who are blue is different from 25%}

The test statistics that will be used here is One-sample z proportion statistics;

T.S. = $\frac{\hat p-p}{{\sqrt{\frac{\hat p(1-\hat p)}{n} } } } }$ ~ N(0,1)

where, $\hat p$ = sample proportion of 600 cars in San Francisco who are blue = $\frac{141}{600}$ = 0.235

n = sample of cars = 600

So, test statistics = $\frac{0.235-0.25}{{\sqrt{\frac{0.235(1-0.235)}{600} } } } }$

= -0.866

Now at 0.05 significance level, the z table gives critical values of -1.96 and 1.96 for two-tailed test. Since our test statistics lies within the range of critical values of z so we have insufficient evidence to reject our null hypothesis as it will not fall in the rejection region due to which we fail to reject our null hypothesis.

Therefore, we conclude that 25% of all cars in San Francisco are blue which means the dealer's claim was correct.

4 0

3 years ago

The low temperatures last week, in degrees Fahrenheit, were 30, 35, 40, 41, 42, 45, and 47.

puteri [66]

<h3>Answer:</h3>

40

<h3>Step-by-step explanation:</h3>

The average of a data set is the number "in the middle" of all of the numbers. This is a measurement of the center of a data set. Another word for average is mean.

How to Calculate the Average

The average or mean is calculated by adding all of the values together. Then, divide this sum by the number of data points. For example, if the sum of 5 different data points is 10, then the average would be 10/5.

Finding the Average

Now, let's find the average of this specific data set. First, add all of the data together.

30+35+40+41+42+45+47 = 280

Then, count the number of terms. There are 7 different terms within this data set. So, next divide the sum by the number of terms.

280/7 = 40

This means that the average of the set is 40.

Other Measurements of Center

The mean is not the only measurement of center. There are 3 common measures of center.

The mean is found by adding all the terms and then dividing by the number of terms.
Another measurement is the median is found by ordering the terms from least to greatest, and then taking whatever number is left in the middle. The median of this set is 41.
Finally, the mode is the term that appears the most often. Many times there can be more than one mode. This set has no real mode because all of the terms only appear once.

7 0

2 years ago

Simplify each expression.

MrRa [10]

1)B -26-27x
steps :distribute ,-9 times 3 =-27 , -9 times 3x = -27x , now combine like terms :you have a 1 and a -27 ,1-27=-26,and you left with -27

2)D 11-49x
steps :distribute , positive 7 times 1= 7 and then positive 7 times negative 7x =-49, now combine like terms ,since you have a positive 4 combine it with positive 7 which is 11 and finally put it together with -49x which it would look like 11-49x

6 0

3 years ago