 <translate> 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. <yor> Oliver lo 1 / 3 x 135 = 45 àwọn ohun tí a fi ń dáná. Nítorí náà, 135 - 45 = 90 ni àfikún tí ó kù. Ọ̀rẹ́ rẹ̀ yìí gba 2 / 5 x 90 = 36 ọ̀pá. Nítorí náà, Oliver ní 90 - 36 = 54 ọ̀pá ìdánimọ̀. Nítorí náà, ìdáhùn náà ni 54. 