The document discusses calculating the circumference of circles. It provides the formulas for circumference as either 2πr or πd, where r is the radius, d is the diameter, and π is approximately 3.14. It then works through two examples of using the formulas to find the circumference of circles with a radius of 14 cm and a diameter of 20 cm, calculating the answers as 88 cm and 62.8 cm respectively.

2. Supriyadi, S.Pd. Gr

3. Supriyadi, S.Pd. Gr

4. Panjang 1x
lintasan yang
hamster
lalui?
Supriyadi, S.Pd. Gr

5. Supriyadi, S.Pd. Gr
K = 2 x π x r
atau
K = π x d
k = keliling
r = jari-jari lingkara
d = diameter lingkaran
π = phi (3,14 atau
𝟐𝟐
𝟕
)

6. Supriyadi, S.Pd. Gr
14 cm
Tentukan
keliling
lingkaran
tersebut !

7. Supriyadi, S.Pd. Gr
14 cm
Jawab:
diketahui,
jari-jari (r) = 14 cm
Phi (π) = 3,14 atau
𝟐𝟐
𝟕
Keliling = 2 x π x r
= 2 x
𝟐𝟐
𝟕
x 14 cm
= 88 cm

8. Supriyadi, S.Pd. Gr
Keliling lingkaran
dengan panjang diameter
20 cm adalah ...
Keliling = π x d
= 3,14 x 20 cm
= 62,8 cm

9. Supriyadi, S.Pd. Gr