помогите : а)(7/15 + 7/30 + 4/5 ) : ( 2 - 1/3 - 1/2) б) (1/6 + 1/10 + 1/15) : (3/5 + 1/3 - 1/4)
а)(14/30+7/30+24/30):(12/6-2/6-3/6)
45/30:7/6
45/30*6/7=45/35=45/35=9/7=1 2/7
б)(10/60+6/60+4/60):(9/15+5/15-1/4)
20/60:(14/15-1/4)
20/60:29/60
20/60*60/29=20/29