18/37+8/24+19/37-47/24+2/3
18/37 +8/24+19/37-47/24+23
giúp ạ
18/37 + 8/24 + 19/37 - 1va23/24 + 3/8
18/37+8/24+19/37
=(18/37+19/37)+8/24
=1+1//3
=4/3
18/37 +8/24+19/37 -1
=(18/37+19/37)+8/24-1
=1+8/24-1
=(1-1)+8/24
=0+8/24
=8/24
b) 23/24+3/8
=23/24+(3x3/8x3)
=23/24+9/24
=4/3
tính hợp lí
\(\dfrac{18}{37}+\dfrac{8}{24}+\dfrac{19}{37}-1\dfrac{23}{24}+\dfrac{2}{3}\)
\(\left(\dfrac{18}{37}+\dfrac{19}{37}\right)+\left(\dfrac{8}{24}-\dfrac{47}{24}\right)+\dfrac{2}{3}=\dfrac{37}{37}-\dfrac{13}{8}+\dfrac{2}{3}=\dfrac{1}{24}\)
Tính nhẩm: 1) 373737 . 73 - 37 . 737373 2)19 . 41414141 - 41 . 19191919 3)123456 . 456789456789 - 456789 . 123456123456 4)250 . 12 . 7 5)24 . 125 . 9 6)125 . 44 . 18 7)8 . 24 . 6 + 12 . 4 . 52 + 2 . 22 . 24 8)18. 58 . 2 - 9 . 27 . 4 + 12 . 69 . 3 9)30 . 85 . 3 + 18 . 72 . 5 - 45 . 37 . 2 - 9 . 20 . 10
1) \(373737.73-37.737373\)
\(=37.10101.73-37.73.10101\)
\(=0\)
2) \(19.41414141-41.19191919\)
\(=19.41.1010101-41.19.1010101\)
\(=0\)
3) \(123456.456789456789-456789.123456123456\)
\(=123456.456789.1000001-456789.123456.1000001\)
\(=0\)
4) \(250.12.7\)
\(=250.4.3.7\)
\(=\left(250.4\right).\left(3.7\right)\)
\(=1000.21\)
\(=21000\)
5) \(24.125.9\)
\(=3.8.125.9\)
\(=\left(3.9\right).\left(8.125\right)\)
\(=27.1000\)
\(=27000\)
6) \(125.44.18\)
\(=125.4.11.2.9\)
\(=\left(125.4.2\right).\left(11.9\right)\)
\(=1000.99\)
\(=99000\)
7) \(8.24.6+12.4.52+2.22.24\)
\(=48.24+48.52+48.22\)
\(=48\left(24+52+22\right)\)
\(=48.98\)
\(=48\left(100-2\right)\)
\(=48.100-48.2\)
\(=4800-96\)
\(=4704\)
8) \(18.58.2-9.27.4+12.69.3\)
\(=36.58-36.27+36.69\)
\(=36\left(58-27+69\right)\)
\(=36.100=3600\)
9) \(30.85.3+18.72.5-45.37.2-9.20.10\)
\(=90.85+90.72-90.37-90.20\)
\(=90\left(85+72-37-20\right)\)
\(=90.100=9000\)
\(\frac{18}{37}+\frac{8}{24}+\frac{19}{37}-1\frac{23}{24}+\frac{2}{3}\)
(( MN ƠI GIÚP MIK nha ))
(( MIK ĐANG CẦN LẮM ))
18/37 + 8/24 + 19/37 - 1/23/24 + 2/3
= 18/37 + 19/37 + 1/3 + 2/3 - 1/23/24
= 1 + 1 - 1/23/24
= 2 - 1/23/24
= 1/24
( chú ý : 1/3 là rút gọn của 8/24 )
\(\frac{18}{37}+\frac{8}{24}+\frac{19}{37}-1\frac{23}{24}+\frac{2}{3}\)
\(=\frac{18}{37}+\frac{1}{3}+\frac{19}{37}-1\frac{23}{24}+\frac{2}{3}\)
\(=\left(\frac{18}{37}+\frac{19}{37}\right)+\left(\frac{1}{3}+\frac{2}{3}\right)-1\frac{23}{24}\)
\(=1+1-1\frac{23}{24}\)
\(=2-1\frac{23}{24}=\frac{1}{24}\)
\(\frac{18}{27}+\frac{8}{24}+\frac{19}{37}-1\frac{23}{24}+\frac{2}{3}\)
\(=\frac{18}{27}+\frac{8}{24}+\frac{19}{37}-\frac{47}{24}+\frac{16}{24}\)
\(=\left(\frac{18}{37}+\frac{19}{37}\right)+\left(\frac{8}{24}+\frac{16}{24}\right)-\frac{47}{24}\)
\(=\frac{37}{37}+\frac{24}{24}-\frac{47}{24}\)
\(=1+1-\frac{47}{24}\)
\(=2-\frac{47}{24}\)
\(=\frac{48}{24}-\frac{47}{24}\)
\(=\frac{1}{24}\)
bo ngoac roi tinh
- (-15) – (-3 +15 – 8)
b) + ( - 143 + 17 – 35) – ( -143 + 37 – 35)
c) 50 – (47 + 50 – 18) - (+47 + 18)
d) 16 – (-15) + (-20) - | -24 |
- (-15) – (-3 +15 – 8)
= 15 + 3 - 15 + 8
= 11
b) + ( - 143 + 17 – 35) – ( -143 + 37 – 35)
= -143 + 17 - 35 + 143 - 37 + 35
= -20
c) 50 - ( 47 + 50 - 18 ) - ( 47 + 18 )
= 50 - 47 - 50 + 18 - 47 - 18
= -47 - 47
= -94
d) 16 - ( -15 ) + ( -20 ) - | -24 |
= 16 + 15 - 20 - 24
= -13
a, -(-15) - ( -3 + 15 - 8 ) = 15 - 3 + 15 + 8
= 12 + 15 + 8
= 27 + 8
= 35
b, + ( -143 + 17 - 35 ) - ( -143 + 37 - 35 )
= -143 + 17 - 35 + 143 - 37 + 35
= ( -143 + 143 ) + [ 17 + (-37 )] + ( -35 + 35)
= 0 + 20 + 0
= 20
c, 50 - ( 47 + 50 -18 ) - ( +47 + 18 )
= 50 - 47 - 50 + 18 - (-47) - 18
= ( 50 - 50 ) - [ 47 - (-47)] + (18 - 18 )
= 0 - 0 + 0
= 0
d, 16 - (-15) + (-20) -I -24 I
= 16 + 15 - 20 + 24
= 30 - 20 + 24
= 10 + 24
= 34
Tính giá trị biểu thức:
\(e,\dfrac{18}{37}+\dfrac{8}{24}+\dfrac{19}{37}-1\dfrac{23}{24}+\dfrac{2}{3}\)
\(f,\left(-2\right)^3.\left(\dfrac{3}{4}-0,25\right):\left(2\dfrac{1}{4}-1\dfrac{1}{6}\right)\)
\(g,\left(\dfrac{2}{5}\right)^2+5\dfrac{1}{2}.\left(4,5-2\right)+\dfrac{2^3}{\left(-4\right)}\)
\(h,\dfrac{4}{9}.19\dfrac{1}{3}-\dfrac{4}{9}.39\dfrac{1}{3}\)
\(i,\left(-\dfrac{1}{2}\right)^2:\dfrac{1}{4}-2\left(-\dfrac{1}{2}\right)^2\)
\(j,125\%.\left(\dfrac{-1}{2}\right)^2:\left(1\dfrac{5}{16}-1,5\right)+2008^0\)
\(k,\left(-2\right)^3.\dfrac{-1}{24}+\left(\dfrac{4}{3}-1\dfrac{5}{6}\right):\dfrac{5}{12}\)
e: \(=\left(\dfrac{18}{37}+\dfrac{19}{37}\right)+\left(\dfrac{8}{24}+\dfrac{2}{3}\right)-\dfrac{47}{24}=2-\dfrac{47}{24}=\dfrac{1}{24}\)
f: \(=-8\cdot\dfrac{1}{2}:\left(\dfrac{9}{4}-\dfrac{7}{6}\right)\)
\(=-4:\dfrac{13}{12}=\dfrac{-48}{13}\)
g: \(=\dfrac{4}{25}+\dfrac{11}{2}\cdot\dfrac{5}{2}-\dfrac{8}{4}=\dfrac{4}{25}+\dfrac{55}{4}-2=\dfrac{1191}{100}\)
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.