Answer:
4n^2
Step-by-step explanation:
n to the power of 2 (squared), multiplied by 4
Lets get started :)
The First question:
Diameter = 20 ft
Radius =

of 20 (diameter) = 20 ft
Area formula of a circle is
A =

r²
=

(10)²
=100

ft²
≈ 314 ft²The answer will be the second optionThe Second question:
radius of circle = 12mm divided into 20 sectors area
A =

r²
=

(12)²
= 144

ft²
Divide into 20 equal sector areas =
≈ 22.6 mm²Your answer will be the third optionThe Third Question:
90°, sector area = 36

, Radius = ?



and

cancels out
We can now cross multiply
360 × 36 = 90r²
12960 = 90r²
Divide by 90 on either side

144 = r²
Take squareroot
x = 12 inYour answer will be the third option
Solutions
1) <span>Add the whole numbers first ( 7 and 2 )
</span><span>9+<span>7/8</span>+<span>11/12
2) </span></span>Find the Least Common Denominator (LCD) of
<span><span>7 / 8</span>,<span>11 / 12
</span></span>
Start by Listing Multiples
List out all multiples of each denominator, and find the first common one.
8 : <span><span>8,16,24</span>
</span>
12 : <span>12,24
</span>
Therefore, the LCD is <span>24
</span>Method 2: By Prime Factors
List all prime factors of each denominator, and find the union of these primes.
8 : <span>2,2,2
</span>
12 : <span>2,2,3
</span>
Therefore, the LCD is <span>2×2×2×3=24
3) </span>Make the denominators the same as the LCD
<span>9+<span><span>7×3 / </span><span>8×3</span></span>+<span><span>11×2 / </span><span>12×2
</span></span></span>4) Simplify. Denominators are now the same
<span>9+<span>21 / 24</span>+<span>22 / 24
5) J</span></span>oin the denominators
<span>9+<span><span>21+22 / </span>24</span></span>
6) Simplify
<span>9+<span>43 / 24
7) </span></span>Convert 43 / 24 <span>to mixed fraction
</span><span>9+1 <span>19 / 24
8) </span></span>Simplify
<span><span>10 <span>19 / 24</span></span></span>