1) (6.83 + 3.17) + (7.81 + 8.19) = 26
2) 527 + (925-825) = 627
3)
= 2610
4)
5)
6) (-5.37+(-4.37)) + 9.29 = (-0.45)
7)
8)
4м8дм9см+2м7дм=7м5дм9см
или 7м59см
9,8х+12,6-27,6=10,1х
9,8х-10,1х=15
-0,3х=15
х=-50
7(1,4*(-50)+1,8)-27,6=10,1*(-50)
7(-70+1,8)-27,6=-505
-505=-505
-2,1х+56+1,2х+15=59,5
-0,9х+71=59,5
-0,9х=59,5+71
-0,9х=130,5
х=130,5/0,9
х=-145