Khảo sát năng lực giáo viên tiểu học huyện sông mã năm học 2013 - 2014 dành cho giáo viên tiểu học

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Câu 12 :( 6 điểm). Cho hình thang vuông ABCD ( như hình vẽ ) có đáy bé bằng đáy lớn, có diện tích bằng 72 cm2 . Tính diện tích tam giác ABD. 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Câu 6: Toán lớp 5 :( 6 điểm). Cho hình chữ nhật ABCDcó: điểm E nằm trên cạnh AB, điểm M nằm trên cạnh BC Biết rằng: EB = 28 cm; MB = ½BC = 14cm ; CD = 84 cm. Tính diện tích tam giác EDM. Hình vẽ Tóm tắt ................................................................................... ……... ……………………………………………………………… ……………………………………………………………… ................................................................................... ……... ……………………………………………………………… ……………………………………………………………… ................................................................................... ……... ……………………………………………………………… ……………………………………………………………… ................................................................................... ……... ……………………………………………………………… ……………………………………………………………… ................................................................................... ……... ……………………………………………………………… ……………………………………………………………… Lời giải ................................................................................... ……................................... …………………………………………………………………………………… ………………………………………………………………………………….. ................................................................................... ……................................... …………………………………………………………………………………… ………………………………………………………………………………….. ................................................................................... ……................................... …………………………………………………………………………………… ………………………………………………………………………………….. ................................................................................... ……................................... …………………………………………………………………………………… ………………………………………………………………………………….. ................................................................................... ……................................... …………………………………………………………………………………… ………………………………………………………………………………….. ................................................................................... ……................................... …………………………………………………………………………………… ………………………………………………………………………………….. Câu 4: (1 điểm) Bài giải Chu vi gồm 2 chiều dài và 2 chiều rộng Theo đầu bài, chu vi gấp 5 lần chiều rộng, nên ta có sơ đồ: rộng rộng rộng rộng rộng Chu vi dài x 2 Nhìn vào sơ đồ ta thấy 2 chiều dài ứng với 3 chiều rộng. Vậy chiều rộng của hình chữ nhật đó là: (60 x 2) : 3 = 40 (m) Đáp số: 40 m