I don’t understand question 2 a, b, c, d and e plz help

A house was bought in 20000 and sold in 50000 . calculate it's percentage

qaws [65]

Answer:

appreciated value 2.5%

4 0

3 years ago

Lin rode her bike 2 miles in 8 minutes. She rode at a constant speed. Complete the table to show how long it took her to travel

I am Lyosha [343]

Answer:d

1/4 minute

Step-by-step explanation:i hop this helps

5 0

3 years ago

PLEASE HELPPPPPPPPPPPPPPPPPP

jeka94

Step-by-step explanation:

vid of you five minutes

3 0

3 years ago

Two students in different classes took the same math test. Both students received a

ivann1987 [24]

Answer:

Both students scored in the top 10% of their classes.

Step-by-step explanation:

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the z-score 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 p-value, we get the probability that the value of the measure is greater than X.

In this question:

Top 10% = Above the 100 - 10 = 90th percentile.

The 90th percentile of scores is X when Z has a pvalue of 0.9, that is, Z = 1.28.

So, the student who had a z-score above 1.28 scored in the 90th percentile of their class.

In student A's class the mean was 78 and the standard deviation of 5. He scored 87.

We have that $\mu = 78, \sigma = 5, X = 87$

Then

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

$Z = \frac{87 - 78}{5}$

$Z = 1.8$

1.8 > 1.28, so student A scored in the top 10% of his/her class.

Student B's class the mean was 76 with a standard deviation of 4. Scored 87.

We have that $\mu = 76, \sigma = 4, X = 87$

Then

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

$Z = \frac{87 - 76}{4}$

$Z = 2.75$

2.75 > 1.28, so student B also scored in the top 10% of his/her class.

Both students scored in the top 10% of their classes.

8 0

3 years ago

Reimann Sum... I got it wrong twice... Please help and provide step by step clear explaination. I'd appreciate it.

AnnyKZ [126]

Formula for Riemann Sum is:
$\frac{b-a}{n} \sum_{i=1}^n f(a + i \frac{b-a}{n})$
interval is [1,3] so a = 1, b = 3
f(x) = 3x , sub into Riemann sum

$\frac{2}{n} \sum_{i=1}^n 3(1 + \frac{2i}{n})$

Continue by simplifying using properties of summations.
$= \frac{2}{n}\sum_{i=1}^n 3 + \frac{2}{n}\sum_{i=1}^n \frac{6i}{n} \\ \\ = \frac{6}{n}\sum_{i=1}^n 1 + \frac{12}{n^2}\sum_{i=1}^n i \\ \\ =\frac{6}{n} (n) + \frac{12}{n^2}(\frac{n(n+1)}{2}) \\ \\ =6+\frac{6}{n}(n+1) \\ \\ =12 + \frac{6}{n}$

Now you have an expression for the summation in terms of 'n'.

Next, take the limit as n-> infinity.
The limit of $\frac{6}{n}$ goes to 0, therefore the limit of the summation is 12.

The area under the curve from [1,3] is equal to limit of summation which is 12.

7 0

3 years ago