All categories

2 years ago

I need help with this pleasee

Mathematics

2 answers:

Galina-37 [17]2 years ago

7 0

The answer Above is correct

Vedmedyk [2.9K]2 years ago

6 0

He walked 45 mins and burned 250 i think hope i helped

You might be interested in

A certain number added to its square is 30. Find the number

Alex Ar [27]

X+x²=30
x²+x-30=0
(x+6)(x-5)=0
x=-6 or x=5

5 0

2 years ago

2. In your own words, explain HOW to find the standard deviation of this data set. (20 points) 3. What does the standard deviati

Ket [755]

Answer:

$\sigma = 11.28$ --- Standard deviation

Step-by-step explanation:

Given

See attachment for graph

Solving (a): Explain how the standard deviation is calculated.

<u>Start by calculating the mean</u>

To do this, we divide the sum of the products of grade and number of students by the total number of students;

i.e.

$\bar x = \frac{\sum fx}{\sum f}$

So, we have:

$\bar x = \frac{50 * 1 + 57 * 2 + 60 * 4 + 65 * 3 +72 *3 + 75 * 12 + 77 * 10 + 81 * 6 + 83 * 6 + 88 * 9 + 90 * 12 + 92 * 12 +95 * 2 + 99 * 4 + 100 * 5}{1 + 2 + 4 + 3 +3 + 12 + 10 + 6 + 6 + 9 + 12 + 12 +2 + 4 + 5}$

$\bar x = \frac{7531}{91}$

$\bar x = 82.76$

Next, calculate the variance using the following formula:

$\sigma^2 = \frac{\sum f(x - \bar x)^2}{\sum f}$

i.e subtract the mean from each dataset; take the squares; add up the squares; then divide the sum by the number of dataset

So, we have:

$\sigma^2 = \frac{1 * (50 - 82.76)^2 +...................+ 5 * (100 - 82.76)^2}{91}$

$\sigma^2 = \frac{11580.6816}{91}$

$\sigma^2 = 127.26$

Lastly, take the square root of the variance to get the standard deviation

$\sigma = \sqrt{\sigma^2}$

$\sigma = \sqrt{127.26}$

$\sigma = 11.28$ --- approximated

<em>Hence, the standard deviation is approximately 11.28</em>

Considering the calculated mean (i.e. 82.76), the standard deviation (i.e. 11.28) is small and this means that the grade of the students are close to the average grade.

8 0

2 years ago

Explain (in words) what you would do to find the missing value in the equation. You do not find the missing number! Equation: ?

maks197457 [2]

Answer:

The missing value = $23\frac{1}{24}$

Step-by-step explanation:

Given - Equation: ? + 59 5/8= 82 2/3

To find - Explain (in words) what you would do to find the missing value in

the equation. You do not find the missing number.

Proof -

Let the missing number = x

So, the equation becomes x + $59\frac{5}{8}$ = $82\frac{2}{3}$

⇒x = $82\frac{2}{3}$ - $59\frac{5}{8}$

= $\frac{248}{3} - \frac{477}{8}$

= $\frac{1984 - 1431}{24}$

= $\frac{553}{24}$

= $23\frac{1}{24}$

⇒x = $23\frac{1}{24}$

∴ we get

The missing value = $23\frac{1}{24}$

Explanation -

Here we have given the ? with addition of number that is equation to some number.

We just have to subtract the two numbers to find the missing value , as we do above.

5 0

2 years ago

Here is Laila’s graph from the previous screen.

lidiya [134]

Answer:

y=-1/3x+8

Step-by-step explanation:

There is no need for any specific answers, but here is one that could logically work out. Since the graph is going left/down, it has a negative slope, so -1/3 would be reasonable. The graph doesn't cross the origin and crosses above it, so this equation must have a positive 'b' value. In this case, I chose 8. y=-1/3+8 could represent Laila's graph.

4 0

2 years ago

What is the answer to 3 3/8 - 1 5/6=

Ilya [14]

Answer:

37/24

Step-by-step explanation:

3 0

2 years ago