Răspuns :

1/4+1/4:(1/4+1/4×1/4)×3/4=

=1/4+1/4:(1/4+1/16)×3/4=

=1/4+1/4:(4/16+1/16)×3/4=

=1/4+1/4:5/16×3/4=

=1/4+1/4×16/5×3/4=

=1/4+4/5×3/4=

=1/4+3/5=

=5/20+12/20=17/20