Вычисли:(7/8 - 4/5)+(1/20+1/4)+1/2=?

(7/8 - 4/5)+(1/20+1/4)+1/2=7/8; ////1)7/8-4/5=35/40-32/40=3/40; ///2)1/20+1/4=1/20+5/20=6/20=3/10; ///3)3/40+3/10=3/40+12/40=15/40=3/8; ///4)3/8+1/2=3/8+4/8=7/8; Ответ: 7/8