Question

2:Tính.

a, 32 + (- 34) + 36 + (-38) + 40 + (-42).

b, 28.49 + 28.61 + 72.35 + 72.75.

Answer 1

câu a dễ tự làm nhaaaa

b, 28.49 + 28.61 + 72.35 + 72.75.

= 28(49+61) + 71(35+75)

=28.110 + 71.110

= 110(28+72)

=110.100=11000

Chúc học tốt^^

nhớ

Answer 2

a,32+(-34)+36+(-38)+40+(-42)=(32-34)+(36-38)+(40-42)=-2-2-2=-6

b, 28.49+28.61+72.35+72.35=28.(49+61)+72.(35+75)=28.110+72.110=110.(28+72)=110.110=12100