Răspuns :

[(7/15+1/3-1/5)×5/4+(1/2-1/4):5/12]×2/7=

=[(7/15+5/15-3/15)×5/4+(2/4-1/4):5/12]×2/7=

=[(12/15-3/15)×5/4+1/4:5/12]×2/7=

=(9/15×5/4+1/4×12/5)×2/7=

=(9/12+3/5)×2/7=

=(3/4+3/5)×2/7=

=(15/20+12/20)×2/7=

=27/20×2/7=27/70

Răspuns:

⇒27/70

Explicație pas cu pas:

[(7/15+1/3-1/5)×5/4+(1/2-1/4):5/12]×2/7=

[(7/15+5/15-3/15)×5/4+(2/4-1/4):5/12]×2/7=

[(12/15-3/15)×5/4+1/4:5/12]×2/7=

(9/15×5/4+1/4×12/5)×2/7=

(9/12+3/5)×2/7=

(3/4+3/5)×2/7=

(15/20+12/20)×2/7=

27/20×2/7=

27/70