All categories

3 years ago

Angelica painted 1/20 of her bedroom walls in 1/2 an hour. How long will it take Angelica to paint her whole bedroom?

2 answers:

4 0

Angelica would have painted the bedroom in 20 hours if every hour she painted 1/20. But she doesn't paint 1/20 of a room per hour but rather 30 minutes. That means it will take her 10 hours to paint the whole room.

Hope this helps.

SpyIntel [72]3 years ago

4 0

Answer:

10 hours

Step-by-step explanation:

To work this out you would first have to imagine the room as a pizza that is cut into 20 slices. And you can only eat 1 slice every half an hour. To work this out you would first have to convert the fraction of an hour into minutes. You can do this by dividing 60 by 2, which gives you 30. Then you would multiply 30 by 20, which gives you 600. this is because you are calculating how many minutes it would take you to finish. Then depending on if you want that in hours you would divide 600 by 60, which gives you 10. This shows that it will take 10 hours to finish painting the room.

1) Divide 60 by 2.

$60/2=30$

2) Multiply 30 by 20.

$30*20=600$

3) Divide 600 by 60.

$600/60=10 hours$

You might be interested in

Help ASAP What's the remainder of 8,595 ÷ 24?

mart [117]

Answer:

R = 3

Step-by-step explanation:

8595 / 24 = 358.125

24 * 358 = 8568

8595 - 8592 = 3

4 0

2 years ago

An airplane has 100 seats for passengers. Assume that the probability that a person holding a ticket appears for the flight is 0

zmey [24]

Answer:

96.33% probability that everyone who appears for the flight will get a seat

Step-by-step explanation:

I am going to use the binomial approximation to the normal to solve this question.

Binomial probability distribution

Probability of exactly x sucesses on n repeated trials, with p probability.

Can be approximated to a normal distribution, using the expected value and the standard deviation.

The expected value of the binomial distribution is:

$E(X) = np$

The standard deviation of the binomial distribution is:

$\sqrt{V(X)} = \sqrt{np(1-p)}$

Normal probability distribution

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

When we are approximating a binomial distribution to a normal one, we have that $\mu = E(X)$ , $\sigma = \sqrt{V(X)}$ .