1) 43 + (-60) + 12 + 39 + ( -21 ) ; 2) -1,23 + 2,14 + 7,38 + ( -5,77) + 1,62; 3) -3/7 +...

Question

1) 43 + (-60) + 12 + 39 + ( -21 ) ;
2) -1,23 + 2,14 + 7,38 + ( -5,77) + 1,62;
3) -3/7 + 14/19 + ( -4/7 ) + 3 5/19 ;

Answer 1

43 + (-60) + 12 + 39 + ( -21 ) = (43+12)  + +39 - (60+21) = 55 + 39  - 81 = 13
2) -1,23 + 2,14 + 7,38 + ( -5,77) + 1,62 = -(1,23 + 5,77) + (7,38+1,62) + 2,14 =     = -7 + 9 + 2,14 = 4,14

3) -3/7 + 14/19 + ( -4/7 ) + 3 5/19  = -(3/7+4/7) + (14/19 + 3 5/19) = - 1 + 4= 3

Comments

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