=78.(31+24+17)+22.72
=78.72+22.72
=72.(78+22)
=72.100
=7200
l.i.k.e mình nha ngo anh tu
78 . 31 + 78 . 24 + 78 . 17 + 22 . 72
= 78 . (31 + 24 + 17) + 72 . 22
= 78 . 72 + 72 . 22
= 72 . (78 + 22)
= 72 . 100
= 7200
TL:
78 . 31 + 78 . 24 + 78 . 17 + 22 . 72
= 78 . (31 + 24 + 17) + 72 . 22
= 78 . 72 + 72 . 22
= 72 . (78 + 22)
= 72 . 100
= 7200
HT