If you complete the square you get
and as any number squared is positive and 4 is positive, the result must be positive
The side length of the square concrete slab if the area is increased by 25% is 5feet
The formula for calculating the area of a square is expressed as:
A = L² where:
L is the side length of the square
Given the area of the square concrete slab = 20 square feet
20 = L²
L =√20
If the area is increased by 25%, new area will be:
An = 20 + (0.25*20)
An = 20 + 5
An = 25 sq.ft
Get the new length
An = Ln²
25 = Ln²
Ln = √25
Ln = 5feet
Hence the side length of the square concrete slab if the area is increased by 25% is 5feet
Learn more here: brainly.com/question/11300671
Answer:
The largest number of pyramids she can make from 20 bars of chocolate is:
Step-by-step explanation:
Firstly, you must find the volume of the 20 bars of chocolate, remember that each bar contains 6 cubic inches of chocolate (6 in^3), so:
- Volume of the bars = 6 in^3 * 20
- <u>Volume of the bars = 120 in^3</u>
Now, you must find the volume of each pyramid, using the next formula:
- Volume of a pyramid = 1/3 B * h
Where:
<em>B = area of the square base.</em>
<em>h = height of the pyramid.</em>
How these values are given in the problem, we only replace the values in the formula:
- Area of a pyramid = 1/3 (1 in^2) * 2 in
- <u>Area of a pyramid = 2/3 in^3</u>
Finally, we divide the volume of the bars in the volume of each pyramid:
- Total number of pyramids = 120 in^3 / 2/3 in^3
- <u>Total number of pyramids = 180</u>
Answer: - 0.28
Explanation:
1) Expected value: is the weighted average of the values, being the probabilities the weight.
That is: ∑ of prbability of event i × value of event i.
In this case: (probability of getting 2 or 12) × (+6) + (probability of gettin 3 or 11) × (+2) + (probability of any other sum) × (-1).
2) Sample space:
Sum Points awarded
1+ 1 = 2 +6
1 + 2 = 3 +2
1 + 3 = 4 -1
1 + 4 = 5 -1
1 + 5 = 6 -1
1 + 6 = 7 -1
2 + 1 = 3 +2
2 + 2 = 4 -1
2 + 3 = 5 -1
2 + 4 = 6 -1
2 + 5 = 7 -1
2 + 6 = 8 -1
3 + 1 = 4 -1
3 + 2 = 5 -1
3 + 3 = 6 -1
3 + 4 = 7 -1
3 + 5 = 8 -1
3 + 6 = 9 -1
4 + 1 = 5 -1
4 + 2 = 6 -1
4 + 3 = 7 -1
4 + 4 = 8 -1
4 + 5 = 9 -1
4 + 6 = 10 -1
5 + 1 = 6 -1
5 + 2 = 7 -1
5 + 3 = 8 -1
5 + 4 = 9 -1
5 + 5 = 10 -1
5 + 6 = 11 +2
6 + 1 = 7 -1
6 + 2 = 8 -1
6 + 3 = 9 -1
6 + 4 = 10 -1
6 + 5 = 11 +2
6 + 6 = 12 +6
2) Probabilities
From that, there is:
- 2/36 probabilities to earn + 6 points.
- 4/36 probabilites to earn + 2 points
- the rest, 30/36 probabilities to earn - 1 points
3) Expected value = (2/36)(+6) + (4/36) (+2) + (30/36) (-1) = - 0.28
Answer:
Step-by-step explanation:
244
424
What are the concentrations in percent?
x1 =
⇒ 50%
x2 =
⇒ 25%
x3 =
⇒ 5%
172
