Math Calculators, Lessons and Formulas

It is time to solve your math problem

mathportal.org
  • Geometry
  • Circles
  • Circle formulas

Circle formulas

ans:
syntax error
C
DEL
ANS
±
(
)
÷
×
7
8
9
–
4
5
6
+
1
2
3
=
0
.
auto next question
evaluate answers
calculator
  • Question 1:
    1 pts
    		Which expression can be used to find the area of a circle shown on the picture
    $A=16\pi cm^{2}$
    $A=2\cdot8\pi cm^{2}$
    $A=2\cdot 8^{2}\pi cm^{2}$
    $A=8^{2}\pi cm^{2}$
  • Question 2:
    1 pts
    		Which expression can be used to find the perimeter of a circle shown on the picture.
    $P=4\pi cm$
    $P=2\cdot4\pi cm$
    $P=2\cdot 4 cm$
    $P=4^{2}\pi cm$
  • Question 3:
    1 pts
    		Find the arc length of an arc formed by $36^{\circ}$ of a circle with a radius of $5$ inches.
    $l=\dfrac{5^{2}\pi 36^{\circ}}{360^{\circ}}$
    $l=\dfrac{10\pi 36^{\circ}}{360^{\circ}}$
    $l=\dfrac{5\pi 36^{\circ}}{360^{\circ}}$
    $l=\dfrac{10\pi 360^{\circ}}{36^{\circ}}$
  • Question 4:
    1 pts
    		Which expression can be used to find the area of a sector,$A_{s}$, shown on the picture.
    $A_{s}=\dfrac{1.5\cdot \pi\cdot 72^{\circ}}{360^{\circ}}$
    $A_{s}=\dfrac{(1.5)^{2}\cdot \pi\cdot 72^{\circ}}{180^{\circ}}$
    $A_{s}=\dfrac{(1.5)^{2}\cdot \pi\cdot 72^{\circ}}{360^{\circ}}$
    $A_{s}=\dfrac{1.5\cdot \pi\cdot 72^{\circ}}{180^{\circ}}$
  • Question 5:
    2 pts
    		The area of the sector is $18\pi cm^{2}$. Find the length of $x.$
    $x=$
  • Question 6:
    2 pts
    		A path $8 m$ wide surrounds a circular lawn whose diameter is $110 m.$ Which expression can be used to find the area of the path.
    $A=\pi \cdot\left(63^{2}-55^{2}\right)cm^{2}$
    $A=\pi \cdot\left(55^{2}-8^{2}\right)cm^{2}$
    $A=\pi \cdot\left(55^{2}-47^{2}\right)cm^{2}$
    $A=\pi \cdot\left(60^{2}-55^{2}\right)cm^{2}$
  • Question 7:
    2 pts
    		Find the distance between the centres of the circles shown on the picture.
  • Question 8:
    2 pts
    		Find the perimeter of the figure shown on the picture.
    $P=2\cdot(2+2\pi)cm$
    $P=\pi \cdot(2+\pi)cm$
    $P=2\cdot(1+\pi)cm$
    $P=2\cdot(2+\pi)cm$
  • Question 9:
    3 pts
    		Find the area of the shaded figure shown on the picture, if the area of shown rectangle is $32cm^{2}$.
    $A=$
  • Question 10:
    3 pts
    		Find the perimeter of the shaded area shown on the picture.
    $P=\dfrac{24+49\pi}{6}cm$
    $P=\dfrac{25\pi}{6}cm$
    $P=\dfrac{25+48\pi}{6}cm$
    $P=\dfrac{49\pi}{6}cm$
  • Question 11:
    3 pts
    		Find the perimeter of the shaded area shown on the picture, if the radius of the biggest circle is $4cm.$
    $P=$
  • Question 12:
    3 pts
    		Find the perimeter of the shaded area shown on the picture.
    $P=$

Triangle

Quadrilateral

Circle

Polygons