Resolución de ecuaciones en escuelas primarias de People's Education Press.
1)2,64×1,7-2,64×0,7
=2,64×(1,7-0,7)
=2,64×1
=2,64
(2)31,5×1,07-3,15×0,7
=3,15×10,7-3,15×0,7
=3,15×(10,7-0,7)
=3,15 ×10
=31,5
(3)2,7×5,7-2,7 5,3×2,7
=2,7×(5,7-1 5,3)
=2.7×10
=27
(4)0.625÷0.125×0.8
=(0.625×0.8)×8÷(0.128×8 )
=0.5×8÷1
=4
(5)18.6×6.1 3.9×18.6
=18.6×( 6,1 3,9)
=18,6×10
=186
(6)1,3579 3,5791 5,7913 7,9135 9,1357
=(1 3 5 7 9)×1.1111
=25×1.1111
=27.7775
(7)52.5x2.9 5.45
=5.25x29 5,25 0,2
=5,25×(29 1) 0,2
=5,25×30 0,2
=157,5 0,3
=157,7
(8)0.92x15 0.08x15
=(0.92 0.08)×15
=1×15
=15
(9)0,72×1,25×2,5
=0,9×(0,8×1,25)×2,5
=0,9×1×2,5
=2,2510 )
400.6x7-2003x0.4
=200.3x14-200.3x4
=200.3×(14-4)
= 200,3×10
=2003