Answer:
A.
mean = 724.2
Median = 715
Mode = 768
B.
Range = 85
Standard deviation = 29.30
C.
Interval = [665.6, 782.8]
Step-by-step explanation:
Number of samples n = 25
Summation X= 769 + 691 + 699 +730+711+ 765+ 702 718 +719 +712+ 768 +688 +757+695 768 +735 +709 +758 +708+ 693 +736 700+ 687 +772 +715 = 18105
A.
1. Mean = 18105/25
= 724.2
2. Median is the middle value when arranged from the least value to the highest = 715
3. Mode is the number with the highest frequency = 768 (occured two times)
B.
1. Range = highest value - lowest value
Highest value = 772
Lowest value = 687
772-687 = 85
2. Standard deviation = √(X-barX)²/n-1
= √20604/25-1
=√858.5
= 29.30
Please check attachment for the full calculation of the standard deviation
C.
Interval
[Mean - 2(sd), mean + 2(sd)]
= [724.2-2x29.3, 724.2+2x29.3]
=[665.6, 782.8]
Vertical angles are equal to each other:
∠2 = ∠3
5 + 4y = 6y - 25
→ 30 = 2y
→ 15 = y
∠2 = 5 + 4y = 5 + 4(15) = 5 + 60 = 65
linear pairs equal 180:
∠1 + ∠2 = 180
→ ∠1 + 65 = 180
→ ∠1 = 115
Answer 10
This is the formula of an arithmetic sequence.
a
n
=
a
1
+
d
(
n
−
1
)
a
n
=
a
1
+
d
(
n
-
1
)
Substitute in the values of
a
1
=
1
a
1
=
1
and
d
=
3
d
=
3
.
a
n
=
1
+
(
3
)
(
n
−
1
)
a
n
=
1
+
(
3
)
(
n
-
1
)
Simplify each term.
a
n
=
1
+
3
n
−
3
a
n
=
1
+
3
n
-
3
Subtract
3
3
from
1
1
.
a
n
=
3
n
−
2
Answer: x = 50
Concept:
Here, we need to know the idea of alternative interior angles and the angle sum theorem.
<u>Alternative interior angles</u> are angles that are formed inside the two parallel lines, and the values are equal.
The <u>angle sum theorem</u> implies that the sum of interior angles of a triangle is 180°
If you are still confused, please refer to the attachment below or let me know.
Step-by-step explanation:
<u>Given information:</u>
AC ║ DE
∠ABC = 85°
∠A = 135°
<u>Find the value of ∠BAC</u>
∠A + ∠BAC = 180° (Supplementary angle)
(135°) + ∠BAC = 180°
∠BAC = 45°
<u>Find the value of ∠BCA</u>
∠ABC + ∠BAC + ∠BCA = 180° (Angle sum theorem)
(85°) + (45°) + ∠BCA = 180°
∠BCA = 50°
<u>Find the value of x (∠EBC)</u>
∠EBC ≅ ∠BCA (Alternative interior angles)
Since, ∠BCA = 50°
Therefore, ∠EBC = 50°

Hope this helps!! :)
Please let me know if you have any questions
To the nearest thousand is 23,000 and the nearest ten thousand is 20,000