\(a,2\times31\times12+4\times6\times42+8\times27\times3\)
\(=24\times31+24\times42+24\times27\)
\(=24\times\left(31+42+27\right)\)
\(=24\times100\)
\(=2400\)
\(b,583.931+69.\left(170+583\right)+31.170\)
\(=583.931+69.170+69.583+31.170\)
\(=583.\left(931+69\right)+170.\left(69+31\right)\)
\(=583.1000+170.100\)
\(=583000+17000\)
\(=600000\)
\(c,732.976+24.\left(680+732\right)+76.680\)
\(=732.976+24.680+24.732+76.680\)
\(=732.\left(976+24\right)+680.\left(24+76\right)\)
\(=732.1000+680.100\)
\(=732000+68000\)
\(=800000\)
Học tốt
a)2400
b)600000
c)800000
a) 2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3
= 24 x 31 + 24 x 42 + 24 x 27
= 24 x ( 31 + 42 + 27 )
= 24 x 100
= 2400
b) 583 x 931 + 69 x ( 170 + 583 ) + 31 x 170
= 583 x 931 + 69 x 170 + 69 x 583 + 31 x 170
= 583 x ( 931 + 69 ) + 170 x ( 69 + 31 )
= 583 x 1000 + 170 x 100
= 583000 + 17000
= 600000
c) 732 x 976 + 24 x ( 680 + 732 ) + 76 x 680
= 732 x 976 + 24 x 680 + 24 x 732 + 76 x 680
= 732 x ( 976 + 24 ) + 680 x ( 24 + 76 )
= 732 x 1000 + 680 x 100
= 732000 + 68000
= 800000