có một đàn trâu có 5 con bé 9/5 con trưởng thanh số trâu già còn lại là...
ggggggggggggggggggggggggggggggghhhhhhhhhhhhhhhhhggggggggggggggggg
ggggggggggggggggggggggggggggggghhgggggggggggggggggggggggggggggggg
ggggggggggggggggggggggggggggggghhhhhhhhhhhhhhhhhggggggggggggggggg
gggggggggggggggggggggggggggggggggggggggggggggghgggggggggggggggggg
gggggggggggggggggggggggggggggghhhhhhhhhhhhhhhhhgggggggggggggggggg
nhái câu hỏi của tôi à