Question

vòi thứ nhất chảy đầy bể sau 2 giờ vòi thứ 2 có sức chảy =1/3 vòi thứ nhất vòi thứ 3 tháo hết hồ đầy nước trong 4 giờ 2/5 hồ đã có nước người ta cùng mở 1 lúc 3 vòi thì sau bao lâu hồ đầy bể ?giải hẳn ra

Answer 1

Mỗi giờ vòi thứ nhất chảy được: 1 : 2 = 1/2 (hồ)

Mỗi giờ vòi thứ hai chảy được: 1/3 x 1/2 = 1/6 (hồ)

Mỗi giờ vòi thứ ba chảy được: 1 : 4 = 1/4 (hồ)

Mỗi giờ cả 3 vòi chảy được: 1/2 + 1/6 + 1/4 = 11/12 (hồ)

Nếu hồ có 2/5 nước người ta sẽ mở ba vòi trong:

(1 - 2/5) : 11/12 = 36/55 (giờ)

Answer 2

ta có : mk lớp 7 nên ko nhớ nữa

Answer 3

36/55 bạn nhé!mình tính đúng mà

Answer 4

36/55 là đáp số

Answer 5

36/55 sai mk thu rui tren violympic

Answer 6

36/35 gì chứ < mình lại phại đăng nhập lại 2 lần , bực mình ghê

Answer 7

1/4 moi dung

Answer 8

mình chẳng hiểu nổi mấy bạn luôn ơ,đáp án là bao nhiêu vậy?

Answer 9

36/55 là saiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii chắc chắn 10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000% luon

Answer 10

cái nào đây