Question

Một xe máy khởi hành từ A lúc 7 giờ với vận tốc 36km/giờ. Một ô tô cũng khởi hành từ A với vận tốc 800m/phút và đuổi kip xe máy sau 45 phút. Hỏi ô tô khởi hành lúc mấy giờ 

Answer 1

800m/p=40/3m/s=48km/h

45p=3/4h

Quãng đường ô tô đi sau 45p là: 48×3/4=36(km)

Quãng đường xe máy đi sau 45p là: 36×3/4=27(km)

Vậy từ lúc ô tô xuất phát xe máy đã đi đc: 36 - 27 = 9(km)

Ở 9km đó xe máy đi trong thời gian là: 9/36= 1/4(h)

Vậy xe ô tô xuất phát tại A lúc 7h+1/4h=29/4h hay 7h15p

Answer 2

7 giờ 15 đúng 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000%

Answer 3

Thank nhé

Answer 4

7 giờ 15 phút 

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