18 + 25 + 22 + 45
= ( 18 + 22 ) + ( 25 + 45 )
= 40 + 70
= 110
276 + 118 + 324
= ( 276 + 324 ) + 118
= 600 + 118
= 718
18 + 25 + 22 + 45
= ( 18 + 22 ) + ( 25 + 45 )
= 40 + 70
= 110
276 + 118 + 324
= ( 276 + 324 ) + 118
= 600 + 118
= 718
2.Tính bằng cách thuận tiện nhất:
a)18+15+22+45
b)276+118+324
c)5.9.3.2
d)25.5.4.27.2
a) ( x - 25 ) - 110 = 0
b) 124 + ( 118 - x ) = 142
c) 124 - ( 3x + 22 ) = 42
d) x - 32 : 16 = 18
e ) ( x - 32 ) : 16 = 18
f) 294 : ( 19 - 2.x ) = 42
cho a=-47;b=23:c=-15 tinh gia tri bieu thuc
a) a+11-a-59
b) a-b-22+25+b
c) -a-18+c+18-c+b
d) b-5+a-6-c+7-a+8
thuc hien phep tinh
a, A = \(\frac{2004\cdot37+2004+2\cdot2004+2004\cdot59+2004}{324\cdot321-201\cdot324-324+101-18\cdot324}\)
b,M =\(\frac{1+2+2^2+2^3+...+2^{2012}}{2^{2014}-2}\)
1+8+15+22+29+....+407+414
ps nào piết trl nhah cko mih nhé
tinh nhanh 324+[112-(112+324)]
tính nhanh:
a,31.(-18)+31.(-81)-31
b,13.(23+22)-3.(17+28)
c,(-12).47+(-12).52+(-12)
d,-48+48.(-78)+48.(-21)
e,135.(171-123)-171.(135-123)
g,-(-2009+97)-74.(-18)+74.(-118)-2009-3
Tinh nhah
41 x 36 + 59 x 90 + 41 x 84 + 59 x 30
tinh nhanh s= 20*21+22*23+23*24+24*25+...+39*40