150kilogrammes in stones

1 kg = 0.15747 stone (see http://www.metric-conversions.org/weight/kilograms-to-stones.htm) 

so

$${\mathtt{150}}{\mathtt{\,\times\,}}{\mathtt{0.157\: \!47}} = {\mathtt{23.620\: \!5}}$$

150kg ≈ 23.6 stone