The circumference of a circle = π × diameter.

= 3.14 × 24

= 75.36 cm.

The circumference of the basketball hoop is 75.36 cm.

The diameter of the circle is 21 inches.

The circumference of a circle = π × diameter.

The circumference of the circle = 3.14 × 21.

= 65.94 inches

The circumference of the circle is 65.94 inches.

The radius (r) of the circle is 48 cm.

The circumference of the circle = 2 × π × r

= 2 × 3.14 × 48

= 301.44 cm

The circumference of the circle is 301.44 cm.

Evaluate 2πr for r = 5

The circumference of the circle is 10π.

Circumference of the wheel = πd

π × 100

The distance covered by the wheel in one revolution = Circumference of the circle

Number of revolutions of the wheel while travelling 700 cm.

Let r₁ and r₂ be the radii of outer and inner circles.

Circumference of the outer circle, 2πr₁ = 160 m.

Circumference of the inner circle, 2πr₂ = 132 m.

The difference between their radii = 80/π - 66/π

Let d be the diameter of the circle.

The circumference of the circle = πd.

The diameter of a circle is increased by 80%.

The new diameter of the circle = (1 + 0.8) × d = 1.8d

The new circumference of the circle = π × 1.8d = 1.8 π d

The circumference of the circle is increased by 80%.

Let r be the radius of the circle.

The radius of a circle is decreased by 30%.

The new radius of the circle = (1 - 0.3) × r = 0.7r

Circumference of the circle = 2πr

The new circumference of the circle = 2 × π × 0.7r

So, the circumference of the circle is decreased by 30%.

The circumference of a circle = π × diameter

= 3.14 × 25

= 78.50 cm

The circumference of the basketball hoop is 78.50 cm.

Circumference of a circle with diameter d = πd

Circumference of the circle = 2.7cm.

From Steps(1) and (2), πd = 2.7

3 × d = 2.7

3d = 2.7

3d3 = 2.73

d = 0.9

The diameter of the circle is 0.9cm.

The shape of the garden is circle.

Therefore, the distance covered by John = the circumference of the circle.