Find the circumference and area of each. Round to nearest tenth:

Mathematics

1 answer:

patriot [66]2 years ago

8 0

№1. Given: r=8 ft, π≈3.14

C=2×π×r=2×3.14×8=50.24=50.2 ft

A=π×r²=3.14×64=200.96=201 ft²

Answer: 50.2 ft; 201 ft²

№2. Given: D=11 cm, π≈3.14

d=2r or r=2/d, so if d is 11 cm, then r is 11÷2=5.5 cm

C=2×π×r=πD=3.14×11=34.54=34.5 cm

A=π×r²=3.14×(5.5)²=94.985=95 cm²

Answer: 34.5 cm; 95 cm²

You might be interested in

Simplify 3^5/3^2. I do have a basic understanding but I need help on this.

ahrayia [7]

The answer is: " 27 " .
__________________________________________

3⁵ / 3² = 3⁽⁵⁻²⁾ = 3³ = 3 * 3 * 3 = 9 * 3 = 27 .
__________________________________________
-Edit -- Note the following property of exponents : "quotient rule" of exponents:
_____________________________________________
Given that "a" and "b" are positive integers; and that "x" is a real number greater than "zero";
____________________________________________
If a ≥ b , then:

xᵃ /xᵇ = x⁽ᵃ ⁻ ᵇ⁾ ;
____________________________________________
If a 
xᵃ /xᵇ = x⁽ᵇ ⁻ ᵃ⁾
____________________________________________

7 0

3 years ago

A stereo system is being installed in a room with a rectangular floor measuring 13 feet by 11 feet and a 7-foot ceiling. The st

zhuklara [117]

Answer:

about 22.2 feet

Step-by-step explanation:

The wire can run diagonally across the floor and, from the intersection with the wall, diagonally up the wall. The total length is computed per the hint to be ...

d = √(18^2 +13^2) = √493 ≈ 22.20 . . . . feet

___

If the wire were to go up the short wall, its length would be ...

d = √(11^2 +20^2) = √521 ≈ 22.83 . . . . feet

_____

Comment on the attachment

The red represents the floor; the green represents the long wall.

6 0

3 years ago

Edward invested $1600 in a savings account for 8 years. At the end of 8 years, his savings account had $1920 in it.

miss Akunina [59]

$\bf \qquad \textit{Simple Interest Earned Amount}\\\\
A=P(1+rt)\qquad 
\begin{cases}
A=\textit{accumulated amount}\to &\$1920\\
P=\textit{original amount deposited}\to& \$1600\\
r=rate\to r\%\to \frac{r}{100}\\
t=years\to &8
\end{cases}
\\\\\\
1920=1600(1+r8)\implies \cfrac{1920}{1600}=1+8r\implies \cfrac{6}{5}=1+8r
\\\\\\
\cfrac{6}{5}-1=8r\implies \cfrac{\frac{6}{5}-1}{8}=r\implies \cfrac{\frac{1}{5}}{8}=r\implies \cfrac{1}{40}=r
\\\\\\
0.025=r\implies r\%=100\cdot 0.025\implies r=\stackrel{\%}{2.5}$