`@` `\text {Ans}`
`\downarrow`
\(\dfrac{7}{5}\cdot\dfrac{8}{19}+\dfrac{7}{5}\cdot\dfrac{12}{19}-\dfrac{7}{5}\cdot\dfrac{1}{18}\)
`=`\(\dfrac{7}{5}\cdot\left(\dfrac{8}{19}+\dfrac{12}{19}-\dfrac{1}{18}\right)\)
`=`\(\dfrac{7}{5}\cdot\left(\dfrac{20}{19}-\dfrac{1}{18}\right)\)
`=`\(\dfrac{7}{5}\cdot\dfrac{341}{342}=\dfrac{2387}{1710}\)
a) 7/5.8/19+7/5.12/19-7/5.1/19
b)-3/5.5/7+-3/5.3/7+-3/5.6/7
c)10 2/9 + (2 2/5 -7 2/9)
d) 6 3/10 -(3 4/7+ 2 3/10)
GIÚP MÌNH VỚI Ạ. MÌNH CẦN GẤP. CẢM ƠN MỌI NGƯỜI NHÌU!
Tính hợp lý:
a) ( -5/6 + 2/5) : 3/8 + ( 4/5 - 11/30) : 3/8
b) (-3/4 + 2/5) : 3/7 + ( 3/5 + -1/4) : 3/7
c)-13/18 . 5/8 + -5/18 . 2/9 + -13/18 . 3/8 + -5/18 . 7/9
d) -11/19 . 4/9 + -8/19 . 3/7 + -11/19 . 5/9 + -9/19 . 4/7
Tính nhanh:
-5/6.4/19+-7/12.4/19-40/57
-3/7.2/5+2/5.-5/14+18/35
-3/5.(5/17-9/15)-3/5(2/17+-2/5)
2/3.(4/13-9/11)+2/3.(9/13-4/22)
A=4/2.5+4/5.8+4/8.11+...+4/38.41
tính
a, 7/-25 + -18/25 + 4/23 +5/7+19/23
b, 7/19 x 8 /11 + 7/19 x 3/11 + 12/19
c ,day la hon so nha: 8 2/7 -(3 4/7 + 4 2/7 )
d, -7/9 .3/11 + -7 /9.8/11 + 1 7/9
7^20+7^19-7^18 chia hết cho 11
1918 + 1910 + 192 + 193 + 195 : 1918 + 1910 + 192 + 196 + 197 =?
Thực hiện phép tính ( tính nhanh nếu có thể )
1, 11 3/13-(2 4/7+5 3/13)
2, 19 5/8:7/12+(-15 1/4):7/12
3, 2/5.1/3-2 2/15:1/5+3/5.1/3
4, (3 1/3+2,5):(3 1/6-4 1/5)-11/31
5, 75%-1 1/5+0,5:5/12-(-1/2)2
E=1×2×3+2×3×4×3×4×5+...+18×19×20
G=2×4×6+4×6×8+6×8×10+...-18×20×22
H=1×3×5+3×5×7+5×7×9+17×19×21
7/25+(-18)/25+4/23+5/7+19/23
Tính hợp lí.🤔🤔
