Question

find the diameter of the circle whose circumference is 66​

Answer 1

$\bf{\underline{\underline{Question:-}}}$

• find the diameter of the circle whose circumference is 66

$\bf{\underline{\underline{Given:-}}}$

• Circumference of circle is 66

$\bf{\underline{\underline{Find:-}}}$

• Diameter ?

$\bf{\underline{\underline{Formula:-}}}$

$\sf{\boxed{\underline{\red{Circumference\:of\: circle \:is\: \: 2πr}}}}$

$\bf{\underline{\underline{Solution:-}}}$

$\sf → 66 = 2πr$

$\sf → 66 = 2×\frac{22}{7}×r$

$\sf → 66 = \frac{44}{7}×r$

$\sf → 66×7=44r$

$\sf → 462=44r$

$\sf → r = \frac{462}{44}$

$\sf → r = 10.5$

$\bf{\underline{\underline{We\:Know:-}}}$

• Diameter = Radius × 2

$\sf → Diameter = 10.5×2$

$\sf → Diameter = 21$

$\bf{\underline{\underline{Hence:-}}}$

• Diameter of circle is 21

Answer 2

Answer:

Given , circumference =66

now, we know that, circumference of a circle is =2πr .

so, 2πr=66

=>2πr=66

=>2×(22/7)r=66

=>r =66×7/22*2

=>r= 462/44

=>r=10.5

again, we know that

r(radius) =diameter/2

so, diameter (d) =2*r

d=10.5×2

d=21