Possibly so, but you had two context clues in the sentence. 'Le' is female plural, and mangiano is 'they eat' so the sentence referred to more than one girl.
I see your point - we can figure it out; however, here's why we ask for duoLingo to fix it: to 'hear' the incorrect word while looking at the correct word complicates learning the correct pronounciation.
I find that to be a pretty common occurrence. For stuff like that you can notify them directly instead of posting .. it will get duo's moderators' attentions faster (and we can't do much about it except agree with you :-)
It depends on the gender. Le ragazze = all girls. I ragazzi = all boys or mixed gender group. If the gender is not known, use "i ragazzi" for "the children".
I answered it correct, why did i get wrong, i lost a heart for correct answer
"The girls eat cake" was wrong, which I dispute, as "cake" can be plural in English.
Why doesn't it accept my accent at all???? I tried more than 10 times and really what I say is just like what the voice says ...
The girls eat the "PIES"...pies =cakes?? or not?? Cakes=Bolos (in portuguese) or Gatêau (in french)...and Pies= Torta (in portuguese) or Torte in English)