tolong isi cpt Ok cpt

1.
15= 3 x 5
75= 3 x 5²
105= 3 x 5 x 7

KPK dicari faktor terbesar
= 3 x 5² x 7
= 525

2.
π x r x r
22/7 x 21cm x 21cm
1.386cm²