vậy 2 em hs lớp 1 và 1 em hs lớp 2 được số quyển vở là :

2*2+1*1=5

Vậy số cặp là :

135/5=27

số em hs lớp 1 là:

27*2=54 hs

ĐS:54 hs

số học sinh lớp 1 gấp đôi số học sinh lớp 2 nên một nửa số học sinh lớp 1 bằng số học sinh lớp 2

Vì số quyển vở mỗi học sinh lớp 1 gấp đôi số quyển vở mỗi học sinh lớp 2

Nên số quyển vở của một nửa số học sinh lớp 1 cũng gấp đôi số quyển vở cho các học sinh lớp 2

=> Số quyển vở cho cả lớp 1 sẽ gấp 4 lần số quyển vở cho lớp 2

Tổng số quyển vở của 2 lớp là 135

Bài toán : tổng - tỉ: Coi số vở lớp 1 là 4 phần;  số vở lớp 2 là 1 phần

Số vở của lớp 2 là : 135 : (4 +1) x 1 = 27 quyển

Số vở cho lớp 1 là 135 - 27 = 108 quyển

ĐS:...

a

1+1=2

cặp 1

31. the children are playing games, ······················?

32. all the lights went out, ·································?

33. the computer has broken down, ······················?

34. Lan learnt to read as a child, ·························?

35. he seldom goes to church, ····························?

36. your father has bought a bicycle, ····················?

37. nothing is wrong, ······································?

38. it is a nice Sunday, ·····································?

39. Tom and You can run very fast, ·····················?

40. it never works very hard, ······························?

41. I have not got a picture of him, ······················?

42.she smiled to him beautifully, ·························?

43. the doors were locked, ································ ?

44. let’s start this exercise, ································?

45. he does not keep his promise, ························?

46. Jane did not want any dinner, ························?

47. you have not seen this film before, ··················?

48. they are going home, ··································?

49. everything is OK,·······································?

50. I am not having lunch, ································?

51. Linh started working 6 months ago, ·················?

52. Laura had hurt her leg, ································?

53. she wasn’t at home, ···································?

54. my grandmother loved music, ························?

55. they found themselves in the forest, ·················?

56. I think you have seen this once before, ·············?

57. this picture was taken to Paris, ·······················?

58. that must be John’s house, ····························?

59. you have had your hair cut, ···························?

60. today is not Monday, ··································?

61. we took this one last year, ····························?

62. she looks just like Mary, ······························?

63. you can deliver this good to my house, ·············?

64. she is still working there, ·····························?

65. there is a tree in front of my house, ··················?

66. Stand up, ················································?

67. Mai is talking with me, ································?

68. I spend three hours doing my homework, ··········?

69. your bike is stolen, ····································?

70. their dog is over there, ································?

71. tomorrow will be Saturday, ···························?

72. let’s have a look at my new shoes, ···················?

73. we should collect the trashes on the streets, ········?

74. nothing is impossible, ·································?

75. I will try my best, ······································?

76. I am not late for school, ·······························?

77. you did not live in HCM City, ·······················?

78. there will be a building here, ·························?

79. my parents are going to Dalat, ·······················?

80. Tom arrived late, ·······································?

81. I don’t love you, ·······································?

82. I’ve no idea for it, ······································?

83. I think you should come early,························?

84. the film was made in Thailand, ······················?

85. I can play a few simple tune, ·························?

86. my secretary sent the bill to me, ·····················?

87. the president makes the important decisions, ·······?

88. this steak tastes delicious, ····························?

89. wait for me, ·············································?

90. that is your car, ·········································?

91. Andrew has not got many friends, ···················?

92. I do not know, ··········································?

93. it was in 1988, ··········································?

94. my friends come from USA, ·························?

95. you can see it clearly, ·································?

96. you should not drive too fast, ························?

97. I have never seen him before, ························?

98. I am waiting for my love, ·····························?

99. the story was boring, ·································?

100. come and join with us, ····························
Đặt câu hỏi đuôi.

vẽ sơ đồ mạch điện gồm 2 nguồn pin mắc nối tiếp, 2 bóng đèn và 2 khoá k có thể bật tắt riêng biệt