a. 367+129+133+371+17
=(367+133)+(129+371)+17
=500+500+17
=1017
b. 29+132+237+868+763
=29+(132+868)+(237+763)
=29+1000+1000
=2029
c. 652+327+148+15+73
=(652+148)+(327+13)+15
=800+340+15
=1155
a) 367 + 129 + 133 +371 + 17
= ( 367 + 133 ) + ( 129 + 371 ) + 17
= 500 + 500 + 17
= 1017
b) 29 + 132 + 237 + 868 + 763
= ( 132 + 868 ) + ( 763 + 237 ) + 29
= 1000+ 1000 +29
=2029
c) 652 + 327 + 148 + 15 + 73
= ( 652 + 148 ) + ( 327 + 73 ) + 15
= 800 + 400 + 15
=1215
a) 367 + 129 + 133 + 371 + 17;
=(367+133)+(129+371)+17=500+500+17=1017b) 29 + 132 + 237 + 868 + 763;
=29+(132+868)+(267+763)=29+1000+1000=2029c) 652 + 327 + 148 + 15 + 73.
=(652+148)+(327+73)+15=800+400+15=1215a)\(367+129+133+371+17\\ =\left(367+133\right)+\left(129+371\right)+17\\ =500+500+17=1017\)
b)\(29+132+237+868+763\)
\(=\left(132+868\right)+\left(237+763\right)+29\)
\(=1000+1000+29=2029\)
c)\(652+327+148+15+73\)
\(=\left(652+148\right)+\left(327+73\right)+15\)
\(=800+400+15=1215\)
Tính bằng cách nhanh chóng:
a) 367 + 129 + 133 + 371 + 17
= (367 + 133) + (129 + 371) + 17
= 500 + 500 + 17
= 1000 + 17
= 1017
b) 29 + 132 + 237 + 868 + 763
= (132 + 868) + (237 + 763) + 29
= 1000 + 1000 + 29
= 2000 + 29
= 2029
c) 652 + 327 + 148 + 15 + 73
= (652 + 148) + (327 + 73) + 15
= 800 + 400 + 15
= 1200 + 15
= 1215