Question

Calcule as expressões numéricas na forma fracionária e na forma decimal com aproximação para duas casas decimais.
4/5 (3 +0,4) – 3,21
0,22(11-0,3) + 4/7
4/3 + 7/5 (1/2 + 4/9 ) - 1/5
{4 + 2 [32 - 1/4(2/3 - 1/8) + 2] + 16} +1

Answer 1

Boa noite

4/5*(3 +0.4) - 3.21

(4/5)*(34/10) - 321/100 

136/50 - 321/100
272/100 - 321/100 = -49/100 = -4.9 

0.22(11-0.3) + 4/7

(22/100)*(107/10)  + 4.7 

(22*107)/1000 + 4/7 
(7"22*107)/7000 + 4000/7000 

16478/7000 + 4000/7000 = 20478/7000 = 10239/3500 = 2.93
4/3 + 7/5 (1/2 + 4/9 ) - 1/5
4/3 + 7/5 *(17/18) - 1/5 
4/3 + 119/90 - 1/5 
120/90 + 119/90 - 1/5
239/90 - 1/5 = 239/90 - 18/90 = 221/90 = 3.46

{4 + 2 [32 - 1/4(2/3 - 1/8) + 2] + 16} +1
(5 + 2*(32 - 13/96 + 2) + 16) = 4259/48 = 88.73