Jawabanmu

2014-09-02T23:38:54+07:00
84 = 2² × 3 × 7
168 = 2³ × 3 × 7
210 = 2 × 3 × 5 × 7
KPK = 2³ × 3 × 7 × 5
        = 8 × 3 × 7 × 5
        = 840
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:D
2014-09-03T02:26:54+07:00
Kpk dari 84, 168, 210 = 2³ × 3 × 5 × 7 = 840