69+26=?
19+28+28+26+36+69-69-36-26-28-19
\(19+28+28+26+36+69-69-36-26\)\(-28-19\)
=\(19-19+28-28+26-26+36-36+69-69+28\)
=\(0+0+0+0+0+28\)
=\(28\)
$\frac{-3}{26}$+2$\frac{4}{69}$
\(\dfrac{-3}{26}+2\dfrac{4}{69}\)
\(=\dfrac{-3}{26}+\dfrac{142}{69}\)
\(=\dfrac{-3.69}{26.69}+\dfrac{142.26}{26.69}\)
\(=\dfrac{-207+3692}{1794}\)
\(=\dfrac{3485}{1794}\)
69 x 57 = ?
28 + 11 = ?
26 + 19 =?
39 + 6 = ?
69 x 57 = 3933
28 + 11 =39
26 + 19 = 245
39 + 6 = 45
chúc bạn học giỏi !
Tính các tổng sau một cách hợp lí:
a) 1 3 + − 2 6 + 3 9
b) − 4 12 + 18 45 + − 6 9 + 24 30
a) 1 3 + − 1 3 + 1 3 = 1 3
b) − 1 3 + 2 5 + − 2 3 + 4 5 = 1 5
Tính các tổng sau một cách hợp lí:
a) 1 3 + − 2 6 + 3 9
b) − 4 12 + 18 45 + − 6 9 + 24 30
a) 1 3 + − 2 6 + 3 9 = 1 3 + − 1 3 + 1 3 = 1 3
b) − 4 12 + 18 45 + − 6 9 + 24 30 = − 1 3 + 2 5 + − 2 3 + 4 5 = − 1 + 6 5 = 1 5
a. (26-6).(-6)+42.(-7-13)
b. -15.(58-32)-26.(45-69)
c.(-37-17).9+35.(-9-110
d.-25.72+25.21-49.25
a)=20.(-6)+42.(-20)
=-120+(-840)=-960
b)=-15.26-26.(-24)
=-390+624=234
c)=-54.9+35.(-119)
=-486-4165=-4651
d)=25.(-72+21-49)
=25.(-100)=-2500
Tính :
1) ( -35 ). 18 + 28. 35
2) 53. 29 - 47. ( -29 )
3) 125. ( -24 ) + 24. 225
4) 26. ( -121 ) - 121. ( -36 )
5) 65. ( -25 ) + 25. ( -23 )
6) 237. ( -26 ) + 26. 137
7) 30. ( -125 ) + 25. 30
8) ( -37 ). 69 + ( -31 ). 37
9) 31. 72 - 31. 70 - 31.2
10) ( -12 ). 47 + ( -12 ) . 52 + ( -12 )
1) $(-35)\cdot18+28\cdot35$
$=35\cdot(-18)+28\cdot35$
$=35\cdot(-18+28)$
$=35\cdot10$
$=350$
2) $53\cdot29-47\cdot(-29)$
$=53\cdot29-47\cdot(-1)\cdot29$
$=53\cdot29+47\cdot29$
$=29\cdot(53+47)$
$=29\cdot100$
$=2900$
3) $125\cdot(-24)+24\cdot225$
$=(-125)\cdot24+24\cdot225$
$=24\cdot(-125+225)$
$=24\cdot100$
$=2400$
4) $26\cdot(-121)-121\cdot(-36)$
$=-121\cdot[26+(-36)]$
$=-121\cdot(26-36)$
$=-121\cdot(-10)$
$=121\cdot10$
$=1210$
5) $65\cdot(-25)+25\cdot(-23)$
$=-65\cdot25+25\cdot(-23)$
$=25\cdot(-65-23)$
$=25\cdot(-88)$
$=-2200$
6) $237\cdot(-26)+26\cdot137$
$=-237\cdot26+26\cdot137$
$=26\cdot(-237+137)$
$=26\cdot(-100)$
$=-2600$
7) $30\cdot(-125)+25\cdot30$
$=30\cdot(-125+25)$
$=30\cdot(-100)$
$=-3000$
8) $(-37)\cdot69+(-31)\cdot37$
$=37\cdot(-69)+37\cdot(-31)$
$=37\cdot(-69-31)$
$=37\cdot(-100)$
$=-3700$
9) $31\cdot72-31\cdot70-31\cdot2$
$=31\cdot(72-70-2)$
$=31\cdot(2-2)$
$=31\cdot0$
$=0$
10) $(-12)\cdot47+(-12)\cdot52+(-12)$
$=-12\cdot(47+52+1)$
$=-12\cdot100$
$=-1200$
$\text{#}Toru$
Tính bằng cách hợp lý:
286 x 69 + 27 x 286 + 26 x 4 x 11
tính
a\(\dfrac{-3}{26}+2\dfrac{4}{69}\)
\(a)\dfrac{-3}{26}+2\dfrac{4}{69}\)
\(=\) \(\dfrac{-3}{26}\) + \(\dfrac{142}{69}\)
\(=\) \(\dfrac{-207}{1794}\) + \(\dfrac{3692}{1794}\)
\(=\) \(\dfrac{\left(-207\right)+3692}{1794}\)
\(=\) \(1,942586399\)