(2ĐIỂM) A/ 15+17+19+21+23+25 B/ (-21) +(-25) +21 C/ 18.52 +18.48 D/ 30...

Câu 2: (2điểm)

a/ 15+17+19+21+23+25

b/ (-21) +(-25) +21

c/ 18.52 +18.48

d/ 305-(2

3

.3

2

-7

4

:7

2

)