 
<translate> Oliver jiri 1 / 3 x 135 = akwụkwọ mmado 45. Ya mere, e nwere 135 - 45 = 90 akwụkwọ mmado fọdụrụ. Enyi ya natara 2 / 5 x 90 = akwụkwọ mmado 36. N'ihi ya, Oliver debere akwụkwọ mmado 90 - 36 = 54. N'ihi ya, azịza ya bụ 54. <eng> Oliver used 1 / 3 x 135 = 45 stickers. So, there were 135 - 45 = 90 stickers remaining. His friend received 2 / 5 x 90 = 36 stickers. Therefore, Oliver kept 90 - 36 = 54 stickers.
Thus, the answer is 54. 