120 ppb to ppm

120 ppb = 0.12 ppm

ppbppm
105 ppb0.105
110 ppb0.11
115 ppb0.115
1200.12
125 ppb0.125
130 ppb0.13
135 ppb0.135

120 ppb = 0.12 ppm

Formula

1 ppm = 1 mg/L (aqueous, density ≈ 1 kg/L) · 1 ppb = 0.001 mg/L · 1% = 10,000 ppm