b) 394. 1768 + 606. 1769 + 394
c) 1876. 31 + 56. 124 + 25. 1876
d) 2021. 7615 + 2022. 2385 - 1355
e) ( 565656. 79 - 797979. 56 ) 1.2 + 2.3 + 3.4 + ... + 99.100)
Đáp án :
b) 394. 1768 + 606. 1769 + 394
= 394 . ( 1768 + 1) + 606. 1769
= 394 . 1769 + 606. 1769
=1769 . ( 394 + 606 )
= 1769 . 1000
= 1769000
c) 1876. 31 + 56. 124 + 25. 1876
= 1876.(31+25)+56.124
=1876.56+56.124
=56.(1876+124)
= 56.2000
= 112000