f) ; c) ; g) ;18 urgent !!!!! Dau coroana

Răspuns:
c)2/5+4/10+25/75=
2/5+4/10+5/15
2/5+2/5+5/15
6/15+6/15+5/15=17/15
f)325:(36-11)=
325:25=13
g nu stiu cum sa il fac
18. a-b=78,24
3b-b=78,24
2b=78,24
b=39,12
a=3b
a=39,12×3
a=117,36
Verificare:117,36-39,12=78,24