Một người thợ dùng một miếng tôn hình chữ nhật dài 60cm, rộng 40cm để gò thành một cái hộp không nắp. Ông cắt 4 góc của miếng tôn 4 hình vuông bằng nhau có chu vi 48cm. Tính thể tích hộp.

2 câu trả lời

Đáp án:

Chiều rộng miếng tôn :

60 : 3 x 2 = 40 cm

Chiều dài đáy hộp :

60 - 5 x 2 = 50 cm

Chiều rộng đáy hộp :

40 - 5 x 2 = 30 cm

Chiều cao hộp là 5 cm

DT đáy hộp :

30 x 50 = 1 500 cm2

DT mặt trước (hoặc mặt sau) :

50 x 5 = 250 cm2

DT mặt bên :

30 x 5 = 150 cm2

Giải thích các bước giải:

 

Chiều cao của hộp gò là`:`

    `48 : 4 = 12 (cm)`

Thể tích của hộp gò là`:`

    `60 xx 40 xx 12 = 28800 ( cm^3 )`

Đáp số `: 28800 cm^3`

Câu hỏi trong lớp Xem thêm

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