Đáp án:
bài 1
a $\frac{8}{25}$ = 0,32
$\frac{17}{40}$ = 0.425
$\frac{4}{11}$ = 0,(36)
$\frac{5}{12}$ = 0,41(6)
b -0,15 = $\frac{-3}{20}$
0,28 = $\frac{7}{25}$
1,28 = $\frac{32}{25}$
-0,425 = $\frac{-17}{40}$
bài 2
a 0.(3) + 3$\frac{1}{3}$ + 0.4(2)
=0.(3) + 3,(3) + 0.4(2)
= 4,0(2)
b = 0,(4)+ 1,2(31) - 0,(13)
= 1,( 88 )
c = $\frac{13}{18}$
d = $\frac{103}{55}$
