VIRALITY · WORKED K  =  i × c  =  3.5 × 0.20  =  0.70 invites × conversion reach  =  1 + K + K2 + K3 +  = 1 1 − K =  1 1.00 + 0.70 1.70 + 0.49 2.19 + 0.34 2.53 +  → 3.33 Σ =  1 / 0.30  =   3.3× K = 0.7 → paid spend × 3.3 K must be > 1 K amplifies paid too