Question

3) efetue as somas algébrica:
A) 3/2+1,2+2/5+0,4
B) 0,6+8/5+42/5-8,5
C)1/5-3,5-1/4+3,2

Answer 1

a)

$3 \div 2 = 1.5 \\ 2 \div 5 = 0.4 \\ 1.5 + 1.2 + 0.4 + 0.4 = 3.5$

b)

$8 \div 5 = 1.6 \\ 42 \div 5 = 8.4 \\ 0.6 + 1.6 + 8.4 - 8.5 = 2.1$

c)

$0.2 - 3.5 - 0.25 + 3.2 = - 0.35$

Answer 2

A) 3/2+12/10+2/5+4/10

mmc de 2, 5 e 10=> 10

15/10+12/10+4/10+4/10= 35/10 que é 7/2 ou 3,5

B) 6/10+8/5+42/5- 85/10

mmc de 5 e 10 => 10

6/10+16/10+ 84/10-85/10=> 21/10 ou 2,1

C) 1/5- 35/10 -1/4 + 32/10

mmc de 5, 10, 4=> 20

4/20- 130/20- 5/20 + 64/20 =67/20