Question

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Найдите значение выражения : (a + b) + c , если : 1) a = 3,8; b = -5,5; c = -4,5; 2) a = 25,6; b = 18,2; c = 14,4; 3) a = 1/6; b = 2/3; c = -5/8; 4) a = 2 3/8; b = 5 1/4; c = -3 5/12.

Answer 1

1) 3,8-5,5-4,5=3,8-10=-6,2;

2) 25,6+18,2+14,4=40+18,2=58,2;

3) 1/6+2/3-5/8=4/24+16/24-15/24=5/24;

4) $\displaystyle 2\frac{3}{8}+5\frac{1}{4}-3\frac{5}{12}=2\frac{9}{24}+5\frac{6}{24}-3\frac{10}{24}=\\=(2+5-3)+\frac{9+6-10}{24}=4\frac{5}{24};$