25 . 13 . 4 + 2 . 17 . 50
= 25 . 13 + 2 . 17 . 25 . 2
= 25 . 13 +
=100.13+100.17=(13+17).100=30.100=3000
b)=2.48+48.41+48.34
=48.(2+41+34)
=48.77
=3696
25 . 13 . 4 + 2 . 17 . 50
= ( 25 . 4 ) . 13 + ( 50 . 2 ) . 17
= 100 . 13 + 100 . 17
= 1300 + 1700
= 3000
2 . 24 . 2 + 3 . 41 . 16 + 6 . 2 . 8 . 17
= ( 24 . 2 ) . 2 + ( 16 . 3 ) . 41 + ( 8 . 6 ) . ( 17 . 2 )
= 48 . 2 + 48 . 41 + 48 . 34
= 48 . ( 2 + 41 + 34 )
= 48 . 77
= 3696
Câu 1:
25.13.4+2.17.50
=25.13.22+22.17.25
=25.[22(13+17)]
=25.120
=3000
Câu 2:
2.24.2+3.41.16+6.2.8.17
=2.23.3+3.41.24+6.2.23.17
=24.3+24.3.41+24.96
=24.(3+41+96)
=16.140
=2240