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2 years ago

Help again 14 more questions

Mathematics

1 answer:

MArishka [77]2 years ago

5 0

Answer:

A certain element has 25 protons.

Step-by-step explanation:

Please mark brainliest

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QUICKEST AND MOST CORRECT ANSWER GETS BRAINLIEST 0LUS ILL FOLLOW U

RideAnS [48]

Answer:

Step-by-step explanation:

-2x-1 =y

-2x 2= -4-1

= -5

=2, -5

8 0

3 years ago

The marketing department of a sports supply store wants to estimate the percentage of adults in the town who belong to a gym.

velikii [3]

A) If you only sample people in a sports supply store, your sample will be biased. People in a sports supply store are more likely to be people that belong to a gym.
B) While it does not have necessarily the same amount of bias as sampling people in the sports supply store, people that go to a park are generally more likely to be people that exercise or have a gym membership.
C) Taking a random sample of people in town is a good way to get a non-biased sample. They are not necessarily predisposed to answer your question one way or another.
D) For the same reason as choice A, this is a biased sample.

C is the best choice.

4 0

2 years ago

A popcorn company builds a machine to fill 1 kg bags of popcorn. They test the first hundred bags filled and find that the bags

ELEN [110]

Answer:

Step-by-step explanation:

Given that a popcorn company builds a machine to fill 1 kg bags of popcorn. They test the first hundred bags filled and find that the bags have an average weight of 1,040 grams with a standard deviation of 25 grams.

i.e. Sample mean = 1040 and

Sample std dev s = 25 gm

Sample size n = 100

Hence by central limit theorem we have the sample mean follows a normal distribution with mean =1040 and std dev = s = 25 gm

$\bar X = N(1040,25)$

Normal curve would be with mean 1040 and std deviatin 25

b) P(X>1115)

= 1-0.9987

=0.0013

i.e. 0.13% would receive a bag that had a weight greater than 1115 grams

8 0

3 years ago

When two rays show a common endpoint they form an angel true or false

kotegsom [21]

When two rays show a common endpoint they form an angel : TRUE

7 0

3 years ago

An airplane travels 6032 kilometers against the wind in 8 hours and 7312 kilometers with the wind in the same amount of time. Wh

Vladimir79 [104]

Answer:

The rate of plane in still air is 834 km/hr and the rate of wind is 80 km/hr.

Step-by-step explanation:

The airplane travels 6032 km in 8 hours against the wind.

So, $u -v = \frac{6032}{8} = 754$ ........ (1) {Where u is the speed of plane in still air and v is the wind speed}

Again, the airplane travels 7312 km in 8 hours with the wind.

So, $u +v=\frac{7312}{8} =914$ ........ (2)

Now, adding equations (1) and (2) we get,

2u = 1668

⇒ u = 834 km per hour.

So, from equation (1), we get

v = u - 754 = 834 - 754 = 80 km per hour.

Therefore, the rate of the plane in still air is 834 km/hr and the rate of wind is 80 km/hr. (Answer)

3 0

3 years ago