7.8×6.9+2.6×79.3
=2.6x3x6.9+2.6x79.3
=2.6x(20.7+79.3)
=2.6x100
=260
24.6×4.6+2.46×44+246×0.1
=24.6x4.6+24.6x4.4+24.6x1
=24.6x(4.6+4.4+1)
=24.6x10
=246