câu 37
Câu 9: Tính bằng cách thuận tiện nhất:
a) 876 × 64 – 876 × 54 | b) 37 × 25 + 37 × 35 + 37 × 39 + 37 |
Câu 9: Tính bằng cách thuận tiện nhất:
a) 876 × 64 – 876 × 54 |
=>876x(64-54)=876x10=8760
b) 37 × 25 + 37 × 35 + 37 × 39 + 37
37x(25+35+39)=37x99=3663
Chúc em học tốt
a) 876 × 64 – 876 × 54
=(64-54) x 876=10 x 876=8760
b) 37 × 25 + 37 × 35 + 37 × 39 + 37=37 x (25 + 35 + 39)=37 x 99=3663câu 36
câu 37
câu 38
câu 39
câu 40
câu 41
Câu 36: A
Câu 37: D
Câu 38: C
Câu 39: C
Câu 40: B
Câu 41: D
CÂU 37 --> CÂU 40
37. They used to go to school by bike when they were young
38. Quang suggested that they sould visit the Royal Citadel first
39. The car was too expensive for my dad to buy
40. My teacher told me to follow his instruction if I wanted to pass that module
38 Quang suggested that the Royal Citadel should be visited first
39 The car was too expensice for my dad to buy
40 My teacher told me to follow his instructions if I wanted to pass this module
CÂU 37 --> CÂU 40
37 He suggested that Sue buy that picture as an anniversary present for Jack
38 You know the man who sat next to me at the meeting last night, don't you?
39 Covid 19 prevented us from travelling to Da Lat
40 If I had much money, I could buy that house immediately
CÂU 37 --> CÂU 40
37. If he weren't lazy, he wouldn't get bad marks.
38. The boys felt interested in the show.
39. My brother had the vet examined his pet dog last week.
40. Ba suggested that face mask should be worn when going out in public.
37 If he weren't lazy, he wouldn't get bad mark
38 The boys felt interested in the show
39 My brother had the vet examine his pet dog last week
40 Ba suggested that face masks when going out in public
37. If he weren't lazy, he wouldn't get bad mark.
38. The boys felt interested in the show.
39. My brother had the vet examine his pet dog last week.
40. Ba suggested that face masks when going out in public.
Mk có mấy bài toàn cần các bạn giải giúp:
Câu 1: 4/3.7+4/7.11+4/11.15+4/15.19+4/19.23+4/23.27
Câu 2:3/14+3/84+3/204+3/374+3/594+3/864
Câu 3:1/10+1/40+1/88+1/154+1/238+1/340
Câu 4:37/7+37/91+37/247+37/475+37/775+37/1147
Câu 5:1/2+5/6+11/12+19/20+29/30+41/42+55/56+71/72+89/90+109/110
Mk đang cần gấp đề ko sai đâu nha thầy mk cho đấy
Nhớ giải cho mk trong thời gian sớm nhất nhoa
1.\(\frac{4}{3.7}+\frac{4}{7.11}+\frac{4}{11.15}+\frac{4}{15.19}+\frac{4}{19.23}+\frac{4}{23.27}\)
\(=\frac{1}{3}-\frac{1}{7}+\frac{1}{7}-\frac{1}{11}+...+\frac{4}{23}-\frac{4}{27}\)
\(=\frac{1}{3}-\frac{1}{27}=\frac{9}{27}-\frac{1}{27}=\frac{8}{27}\)
2. Đặt \(A=\frac{3}{14}+\frac{3}{84}+\frac{3}{204}+\frac{3}{374}+\frac{3}{594}+\frac{3}{864}\)
\(\Rightarrow A=\frac{3}{2.7}+\frac{3}{7.12}+...+\frac{3}{27.32}\)
\(\Rightarrow5A=3.\left(\frac{5}{2.7}+\frac{5}{7.12}+...+\frac{5}{27.32}\right)\)
\(\Rightarrow5A=3.\left(\frac{1}{2}-\frac{1}{7}+\frac{1}{7}-\frac{1}{12}+...+\frac{1}{27}-\frac{1}{32}\right)\)
\(\Rightarrow5A=3.\left(\frac{1}{2}-\frac{1}{32}\right)\)
\(\Rightarrow5A=3.\frac{15}{32}=\frac{45}{32}\Rightarrow A=\frac{45}{32}:5=\frac{9}{32}\)
3. Đặt \(S=\frac{1}{10}+\frac{1}{40}+\frac{1}{88}+...+\frac{1}{340}\)
\(\Rightarrow3S=\frac{3}{10}+\frac{3}{40}+...+\frac{3}{340}\)
\(\Rightarrow3S=\frac{3}{2.5}+\frac{3}{5.8}+...+\frac{3}{17.20}\)
\(\Rightarrow3S=\frac{1}{2}-\frac{1}{5}+\frac{1}{5}-\frac{1}{8}+...+\frac{1}{17}-\frac{1}{20}\)
\(\Rightarrow3S=\frac{1}{2}-\frac{1}{20}=\frac{9}{20}\Rightarrow S=\frac{9}{20}:3=\frac{3}{20}\)
Câu 1:
\(\frac{4}{3.7}+\frac{4}{7.11}+\frac{4}{11.15}+\frac{4}{15.19}+\frac{4}{19.23}+\frac{4}{23.27}\)
\(\Rightarrow\frac{1}{3}-\frac{1}{7}+\frac{1}{7}-\frac{1}{11}+\frac{1}{11}-\frac{1}{15}+\frac{1}{15}-\frac{1}{19}+\frac{1}{19}-\frac{1}{23}+\frac{1}{23}-\frac{1}{27}\)
\(\Rightarrow\frac{1}{3}-\frac{1}{27}\)
\(=\frac{8}{27}\)
Câu 1:
\(\frac{4}{3\cdot7}+\frac{4}{7\cdot11}+\frac{4}{11\cdot15}+...+\frac{4}{23\cdot27}\)
Áp dụng tính chất \(\frac{b}{a\left[a+b\right]}=\frac{1}{a}-\frac{1}{a+b}\), ta có:
\(\frac{4}{3\cdot7}+\frac{4}{7\cdot11}+\frac{4}{11\cdot15}+...+\frac{4}{23\cdot27}=\frac{1}{3}-\frac{1}{7}+\frac{1}{7}-\frac{1}{11}+\frac{1}{11}-\frac{1}{15}+...+\frac{1}{23}-\frac{1}{27}\)
\(=\frac{1}{3}-\frac{1}{27}=\frac{9}{27}-\frac{1}{27}=\frac{8}{27}\)
Câu 2 tương tự nhưng phải phân
\(\frac{3}{14}+\frac{3}{84}+\frac{3}{204}+...+\frac{3}{864}=\frac{3}{2\cdot7}+\frac{3}{7\cdot12}+\frac{3}{12\cdot17}+...+\frac{3}{27\cdot32}\)
Cái này áp dụng công thức \(\frac{a}{b\left[b+c\right]}=\frac{a}{c}\left[\frac{1}{b}-\frac{1}{b+c}\right]\), ta có:
\(\frac{3}{2\cdot7}+\frac{3}{7\cdot12}+\frac{3}{12\cdot17}+...+\frac{3}{27\cdot32}=\frac{3}{5}\left[\frac{1}{2}-\frac{1}{7}+\frac{1}{7}-\frac{1}{12}+\frac{1}{12}-\frac{1}{17}+...+\frac{1}{27}-\frac{1}{32}\right]\)
\(=\frac{3}{5}\left[\frac{1}{2}-\frac{1}{32}\right]=\frac{3}{5}\cdot\frac{15}{32}=\frac{9}{32}\)
Câu 3:
tương tự quy laautj mẫu là 2.5; 5.8 ....
Câu 4: qL mẫu là 1.7; 7.13; ....
Câu 5: \(=\left[1-\frac{1}{2}\right]+\left[1-\frac{1}{6}\right]+...+\left[1-\frac{1}{110}\right]\)
\(=\left[1-\frac{1}{1\cdot2}\right]+\left[1-\frac{1}{2.3}\right]+\left[1-\frac{1}{3\cdot4}\right]+...+\left[1-\frac{1}{10.11}\right]\)
\(=10-\frac{9}{10}=\frac{91}{10}\)
37*(29-23)-29*(37-23)..................ai giỏi giải jups mik câu này cái...
Câu hỏi: Tính nhanh
1) 25+37-48-25-37
2) 37+35+36+37-14-15-16-17
MỌI NGƯỜI GIÚP MIK NHA!!! CẢM ƠN NHÌU🤗
1) \(25+37-48-25-37=\left(25-25\right)+\left(37-37\right)-48=-48\)
2) \(37+35+36+37-14-15-16-17\)
\(=\left(37-17\right)+\left(35-15\right)+\left(36-16\right)+\left(37-14\right)\)
\(=20+20+20+23=83\)
Câu 4: chia n cho 111 có số dư là 37. Hỏi n có chia hết cho 37 không?
\(n=111k+37=37\left(3k+1\right)⋮37\)
câu 37 thoi ạ