155.5 ppb to ppm

155.5 ppb = 0.155 ppm

ppbppm
140.5 ppb0.141
145.5 ppb0.145
150.5 ppb0.15
155.50.155
160.5 ppb0.161
165.5 ppb0.166
170.5 ppb0.171

155.5 ppb = 0.155 ppm

Formula

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