Jawabanmu

2014-05-12T19:01:01+07:00
1/f = 1/jarak bayangan + 1/jarak benda
1/f = 1/60 cm + 1/12 cm
1/f = 6/60
1/f = 1/10 cm

f= 10 cm (perkalian silang)

Jadi,jarak fokusnya 10 cm

^^