Câu hỏi của Sách Giáo Khoa

Question

Tính nhanh :

a) $2.31.12+4.6.42+8.27.3$

b) $36.28+36.82+64.69+64.41$

Ái Nữ · Accepted Answer

a) 2.31.12+4.6.42+8.27.3= 24.31+24.42+24.27= 24.(31+42+27)=24.100=2400

b) 36.28+36.82+64.69+64.41=36.(28+82)+64.(69+41)=36.110+64.110= (36+64).110=100.110=11000Câu trả lời: a) 2.31.12+4.6.42+8.27.3= 24.31+24.42+24.27= 24.(31+42+27)=24.100=2400

b) 36.28+36.82+64.69+64.41=36.(28+82)+64.(69+41)=36.110+64.110= (36+64).110=100.110=11000

uchihaitachi · Answer

a) 2.31.12+4.6.42+8.27.3

=(2.12).31+(4.6).42+(8.3).27

=24.31+24.42+24.27

=24.(31+42+27)

=24.100

=2400

b)36.28 + 36.82 +64.69 + 64.41

= 36.(28+82) + 64.(69+41)

= 36.110+64.110

=110.(36+64)

=110.100

=11000Câu trả lời: a) 2.31.12+4.6.42+8.27.3