Tính bằng cách thuận tiện nhất
Bài 3. (1 điểm) Tính bằng cách thuận tiện nhất.
1 giờ 45 phút + 105 phút + 1,75 giờ x 8
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1 giờ 45 phút + 105 phút + 1,75 giờ x 8
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