\(42.63+74.21=42.63+37.2.21=42.63+37.42\)
\(=42\left(63+37\right)=42.100=4200\)
42 . 63 + 74 . 21
= 21 . 2 . 63 + 74 . 21
= 21 . 126 + 74 . 21
= 21 . (126 + 74)
= 21 . 200
= 4200
\(42.63+74.21\)
\(=21.2.63+74.21\)
\(=21.126+74.21\)
\(=21\left(126+74\right)\)
\(=21.200\)
\(=4200\)
Chúc bạn học tốt
42.21.3+74.21
=42.3.21+74.21
=126.21+74.21
=(126+74).21
=200.21
=420
Tính nhanh:
42.63+74.21
= 21.2.63+74.21
= 21.126+74.21
= 21. (126+74)
= 21.200
= 4200
.
