-p+2y+3p-(-2y)=-p+2y+3p+2y=4y+2p
-2(k-3)+2(13-k)= -2k+6+26-2k=32-4k
-2(3k-4y)+3(2y-4k)=-6k+8y+6y-12k=-18k+14y
8-(-(5х-1)+2)=8-(-5х+1+2)=8+5х-3=5+5х
Брюки --- х руб
пиджак --- (150+х) руб
пиджак (150+х) --- 100\%
брюки (х) ---- n\%
n\% = х*100 / (150+х)
брюки дешевле пиджака на (100-n)\% = 100 - 100х / (150+х) =
(100*(150+х) - 100х) / (150+х) = 100*150 / (150+х) = 15000 / (150+х)
(2/7+1/4+3/4):8/7=(8+7+21/28):8/7=36/28:8/7=36/28*7/8=36/32=1,125