thực hiện tinh
a,37+42-37+22
b,44:8+23.11
c,6250:{502:[112-(32-22.5)]}
.
thực hiện phép tính
a) 35:4
b) 36:3,2
c) 70:37
d) 23:2,4
a: =8,75
b: =11,25
c: =1 dư 33
d: =115/12=9 dư 7
Câu 37. Cách viết nào sau đây là sai?
A. 3. 32 = 32. B. 24 = 16.
C. 55: 5 = 54 D. 4.45: 42 = 44.
giúp mk với ạ
(7/16 + -1/8 + 9/32) ;5/4
-25/30 x 37/44 + -25/30 x 13/44+-25/30 x -6/44
\(\dfrac{7}{16}+\dfrac{-1}{8}+\dfrac{9}{32}=\dfrac{14}{32}-\dfrac{4}{32}+\dfrac{9}{32}=\dfrac{19}{32}\)
\(\dfrac{5}{4}-\dfrac{25}{30}\times\dfrac{37}{44}+\dfrac{-25}{30}\times\dfrac{13}{44}+\dfrac{-25}{30}\times\dfrac{-6}{44}\)
\(=-\dfrac{25}{30}\times\left(\dfrac{5}{4}+\dfrac{37}{44}+\dfrac{13}{44}-\dfrac{6}{44}\right)\)
\(=-\dfrac{25}{30}\times\left(\dfrac{55}{44}+\dfrac{37}{44}+\dfrac{13}{44}-\dfrac{6}{44}\right)\)
\(=-\dfrac{25}{30}\times\dfrac{99}{44}\)
\(=-\dfrac{5}{6}\times\dfrac{9}{4}\)
\(=-\dfrac{15}{8}\)
\(\left(\dfrac{7}{16}+\dfrac{-1}{8}+\dfrac{9}{32}\right):\dfrac{5}{4}\)
\(=\left(\dfrac{14}{32}+\dfrac{-4}{32}+\dfrac{9}{32}\right):\dfrac{5}{4}\)
\(=\dfrac{19}{32}:\dfrac{5}{4}\)
\(=\dfrac{19}{32}.\dfrac{4}{5}=\dfrac{19.4}{32.5}=\dfrac{19}{40}\)
\(\dfrac{-25}{30}.\dfrac{37}{44}+\dfrac{-25}{30}.\dfrac{13}{44}+\dfrac{-25}{30}.\dfrac{-6}{44}\)
\(=\dfrac{-25}{30}.\left(\dfrac{37}{44}+\dfrac{13}{44}+\dfrac{-6}{44}\right)\)
\(=\dfrac{-25}{30}.\dfrac{44}{44}=\dfrac{-5}{6}.1=-\dfrac{5}{6}\)
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50=?
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50=1275
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50.
Có ai rảnh đâu mà đi ngồi cộng ngần đấy số ra.
Tính:
a) (135-35).(-37)+37.(-42-58)
b) -65.(87-17)-87.(17-65)
c) [3.(-2)-(-8)].(-7)-(-2).(-5)
d) 25.(32+47)-32.(25+47)
e) [3.(-2)-(-8)].(-7)-(-2).(-5)+(-1)^10
a) (135 - 35) . (-37) + 37 . (-42 - 58)
= 100 . 0 . (-100)
= 0
b) -65 . (87 - 17) - 87 . (17 - 65)
= -65 . 70 - 87 . (-48)
= -4550 - 135
= -4415
Bài 7: Tính nhanh
a) 37. 38 + 62. 37 b) 28. 64 + 28. 36
c) 3. 25. 8 + 4. 37. 6 + 2. 38. 12 d) (1200 + 60) : 12
e) 12.53 + 53. 172 – 53. 84 g) (2100 – 42) : 21
h) 39.8 + 60.2 + 21.8 i) 36.28 + 36.82 + 64.69 + 64.41
k) 32. 47 + 32. 53 l) 37.7 + 80.3 +43.7
m) 113.38 + 113.62 + 87.62 + 87.38 n) 123.456 + 456.321 –256
a. 37. 38 + 62. 37
= 37 . (38 + 62)
= 37 . 100
= 3700
b. 28. 64 + 28. 36
= 28 . (64 + 36)
= 28 . 100
= 2800
c. 3. 25. 8 + 4. 37. 6 + 2. 38. 12
= 3 . 8 . 25 + 4 . 6 . 37 + 12 . 2 . 38
= 24 . 25 + 24 . 37 + 24 . 38
= 24 . (25 + 37 + 38)
= 24 . 100
= 2400
Giúp mình giải nhoa :*
Tính nhanh
a)1-3+5-7+9-11+....33-35.
B) (42+43+44+45++47)-(32+33+34+35+36+37)
a,1-3+5-7+9-.......+33-35
=(1+5+9+....+33)-(3+7+11+...+35)
=153-171
=-18
Tick mk vài cái lên 300 mk giải nốt phần b
a) Đặt A=1-3+5-7+9-11+.......+33-35
Ta có: A=(1-3)+(5-7)+.........+(33-35)
=> A=(-2)+(-2)+.........+(-2)
18 số hạng
=> A=(-2).18
=> A=-36
b) Đặt B= (42+43+44+45+36+47)-(32+33+34+35+36+37)
Ta có: B=(42-32)+(43-33)+(44-34)+(45-35)+(47-37)+(46-36)
=> B= 10+10+10+10+10+10
=> B=10.6
=> B=60
Tính:
a) (-37) + (-112)
b) (-42) + 52
c) 13 - 31
d) 14 - 24 - 12
e) (-25) + 30 - 15
a) (–37 ) + (–112)
= –(37 + 112) (cộng hai số nguyên âm).
= –149.
b) (–42) + 52
= 52 – 42 (cộng hai số nguyên khác dấu)
= 10
c) 13 – 31 = –31 + 13 = – (31 – 13) = –18.
d) 14 – 24 – 12 = 14 – (24 + 12) = 14 – 36 = – (36 – 14) = –22.
e) (–25) + 30 – 15 = 30 – 25 – 15 = 30 – (25 + 15) = 30 – 40 = –10