Jawabanmu

2014-05-01T06:54:51+07:00
P = 4 - 100 / PP
   = 4 - 100 / 80
   = 4 - 5/4
   = 16/4 - 5/4
   = 11/4 Dioptri
   = 2,75 D
2014-05-01T07:10:09+07:00
2,75 D

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