All categories

3 years ago

Helpp i really neeed it

Mathematics

1 answer:

Marizza181 [45]3 years ago

7 0

Answer:

9 hours

Step-by-step explanation:

If she makes $ 20 for each car, washing 9 cars in 3 hours would get $ 180.

So she will need to work 9 hours 180 + 180 + 180, washing 9 cars in 3 hours and would get $ 540. This is enough to buy her phone and she will have a surplus of $ 120.

In summary she must work 9 hours

Hope this helps you, please give me the brainliest

You might be interested in

Which number line can you use to simplify 2 - (-8)?

tigry1 [53]

i would say c is the best answer or the 3rd one

3 0

3 years ago

The brand name of Mrs. Fields (cookies) has a 90% recognition rate. If Mrs. fields herself wants to verify that rate by beginnin

Schach [20]

Answer:

0.3874 = 38.74% probability that exactly 9 of the 10 consumers recognize her brand name.

0.6126 = 61.26% probability that the number who recognize her brand name is not nine.

Step-by-step explanation:

For each consumer, there are only two possible outcomes. Either they recognize the name, or they do not. The probability of a customer recognizing the name is independent of anu other customer. This means that the binomial probability distribution is used to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

In which $C_{n,x}$ is the number of different combinations of x objects from a set of n elements, given by the following formula.

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

And p is the probability of X happening.

The brand name of Mrs. Fields (cookies) has a 90% recognition rate.

This means that $p = 0.9$ .

Sample of 10

This means that $n = 10$

Find the probability that exactly 9 of the 10 consumers recognize her brand name.

This is P(X = 9). So

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 9) = C_{10,9}.(0.9)^{9}.(0.1)^{1} = 0.3874$

0.3874 = 38.74% probability that exactly 9 of the 10 consumers recognize her brand name.

Also, find the probability that the number who recognize her brand name is not nine.

1(100%) subtracted by those who recognize. So

1 - 0.3874 = 0.6126

0.6126 = 61.26% probability that the number who recognize her brand name is not nine.

4 0

3 years ago

The original price of a bicycle is $130. The sale price is 60% of the original price. What is the sale price of the bicycle?

djverab [1.8K]

Answer:

$78

Step-by-step explanation:

To find a portion of anything, you just multiply your first item by the equivalent decimal of your percent. Let's put it into action in this problem:

If your original price of your bike is $130, and you are trying to find the sale price, which is 60% (aka 0.6) of your original price. Now, like I previously mentioned, to find the portion of your price, you just want to multiply your OG price (130) by the decimal equivalent of your sale, (0.6). So 130*0.6=78

3 0

3 years ago

Find the value of x

ad-work [718]

Answer:
18

It’s literally 72 divided by 4 which equals 18

7 0

3 years ago

A scuba diver is 23 feet below sea level.A second diver is 7 feet closer to the surface. What integer represents the second scub

NeTakaya

Answer:

The integer is -16

Step-by-step explanation:

The first scuba diver is 23 feet below sea level. THe second is 7 feet closer.

23 - 7 = 16. He is still under sea level, so it would be -16

6 0

3 years ago