Thi khảo sát học sinh giỏi cấp trường thời gian : 150 phút ( không kể thời gian phát đề ) môn : toán 6

Trường THCS Long Vĩnh THI KHẢO SÁT HỌC SINH GIỎI CẤP TRƯỜNG Lớp: 6 Môn : Toán 6 Họ và tên : .. Thời gian : 150 phút ( không kể thời gian phát đề ) Điểm Lời phê Ñeà : Caâu 1 ( 3ñ): Thực hiện phép tính a) 22 . 23 + 56 : 53 ` b) 15.{ 32 : [ 6 – 5 + 5 ( 9 : 3 ) ]} Caâu 2 (3ñ ) Tìm x, biết: a) 75883 – ( 31200 + x ) = 999 b) 5( 12 – x ) – 20 = 30 c) ( 50 – 6x ) 18 = 23. 32.5 Caâu 3 ( 2ñ): Tìm n để các giá trị sao luôn đúng a) 32. 34. 3n = 310 b) 3n. 34 : 9 = 37 Caâu 4 (3ñ ): Tính tổng sau a) A = 1 + 3 + 5 + ... + 2001 b) S = 5 + 10 + 15 + ... + 2015 c) B = 49 + 47 + 45 + 43 + .. . + 1 Câu 5 ( 2ñ ) Tính nhanh a) 463 + 318 + 137 + 22 b) 189 + 424 +511 + 276 + 55 c) 9. 4. 25. 8. 125 d) 32. 4. 125. 25 Caâu 6 (2ñ ): Gäi A lµ tËp hîp c¸c sè tù nhiªn cã 3 ch÷ sè. Hái tËp hîp A cã bao nhiªu phÇn tö? Caâu 7 ( 1ñ ): Tìm điều kiện của x để A = 12 + 15 + 21 + x ( x N ) chia hết cho 3. Caâu 8 ( 4ñ ): Điểm C nằm giữa hai điểm A và B, điểm M nằm giữa hai điểm A và C, điểm N nằm giữa hai điểm C và B. Tia CM trùng với tia nào? Tia CN trùng với tia nào? Dùng lập luận chứng tỏ rằng hai tia CM, CN đối nhau. Bài làm ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ .................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................