chay trong :
1:(1/4-1/6)=12
D/S:12
k nha!
Mỗi giờ vòi thứ nhất chảy được :
1 : 6 = 1/6 ( bể )
Mỗi giờ , cả hai vời chảy được :
1 : 4 = 1/4 ( bể )
Muốn vòi thứ hai chảy đầy bể thì cần :
1 : ( 1/4 - 1/6 ) = 12 ( giờ )
đ/s : 12 giờ
Vòi thứ nhất chảy 6 giờ là đầy. Nhưng cả hai vòi cùng chảy thì vòi thứ nhất chảy 4 giờ là đầy. Vậy 2 giờ còn lại của vòi thứ nhất do vòi thứ hai chảy.
=> vòi thứ hai chảy 4 giờ mới bằng vòi thứ nhất chảy trong 2 giờ.
Vậy vòi thứ hai chảy trong 12 giờ bể sẽ đầy.
Riêng vòi thứ 2 chảy thì sau số giờ để đầy bể là :
1:(1:4-1:6)= 12 (giờ)
Đáp số:12 giờ
12 giờ đó
đúng 10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
12 giờ đúng 100000000000000000000000000000000000% đấy nhé
12 là đúng 100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000%
12 đúng đấy 100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000% luôn
12 đúng 100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000%