tolong bantuin pakai caranya ya

diket:
[tex]\pi = 38.5 \: cm \: = > \: d = \: 77 \: cm[/tex]
ditanya: keliling...?

jawab:
[tex]keliling \: lingkaran \: = \pi \: \times \: d \: = \: \frac{22}{7 } \times 77 = 242 \: cm {}^{2} [/tex]