Bài 1 :
$\frac{9}{4}$ = $\frac{9 x 25}{4 x 25}$ = $\frac{225}{100}$
$\frac{15}{2}$ = $\frac{15 x 5 }{2 x 5}$ = $\frac{75}{10}$
$\frac{18}{30}$ = $\frac{3}{5}$ = $\frac{3 x 2}{5 x 2}$ = $\frac{6}{10}$
$\frac{11}{20}$ = $\frac{11 x 5}{20 x 5}$ = $\frac{55}{100}$
$\frac{5}{200}$ = $\frac{1}{40}$ = $\frac{1 x 25}{40 x 25}$ = $\frac{25}{1000}$
$\frac{4}{400}$ = $\frac{1}{100}$
Bài 2 :
a, 4$\frac{2}{3}$ = $\frac{14}{3}$
6$\frac{6}{10}$ = 6$\frac{3}{5}$ = $\frac{33}{5}$
27$\frac{11}{12}$ = $\frac{335}{12}$
7$\frac{2}{5}$ = $\frac{37}{5}$
b, 15$\frac{1}{3}$ = $\frac{46}{3}$
2$\frac{3}{5}$ = $\frac{13}{5}$
9$\frac{5}{7}$ = $\frac{68}{7}$
2$\frac{4}{9}$ = $\frac{22}{9}$
Bài 3 :
a, 3$\frac{3}{4}$ + 1$\frac{1}{3}$
= $\frac{15}{4}$ + $\frac{4}{3}$
= $\frac{45}{12}$ + $\frac{16}{12}$
= $\frac{61}{12}$
b, 13$\frac{1}{2}$ - 2$\frac{1}{4}$
= $\frac{27}{2}$ - $\frac{9}{4}$
= $\frac{54}{4}$ - $\frac{9}{4}$
= $\frac{45}{4}$
c, 3$\frac{4}{7}$ x 1$\frac{4}{5}$
= $\frac{25}{7}$ x $\frac{9}{5}$
= $\frac{45}{7}$
d, 11$\frac{3}{8}$ : 6$\frac{5}{8}$
= $\frac{91}{8}$ x $\frac{5}{53}$
= $\frac{455}{424}$
Bài 4 :
a, 5$\frac{1}{7}$ > 2$\frac{6}{7}$ ( vì 5 > 2 )
b, 3$\frac{2}{7}$ < 3$\frac{5}{7}$ ( vì $\frac{3}{7}$ < $\frac{5}{7}$ )
c, 8$\frac{6}{10}$ = 8$\frac{3}{5}$ ( vì $\frac{6}{10}$ = $\frac{3}{5}$ )
d, 4$\frac{7}{12}$ < 5$\frac{7}{8}$ ( vì 4 < 5 )
Bài 5 :
a, 8m 5dm = 8m + $\frac{5}{10}$m = 8m + $\frac{1}{2}$ m = 8$\frac{1}{2}$ m
b, 4m 75cm = 4m + $\frac{75}{100}$ m = 4m + $\frac{3}{4}$ m = 4$\frac{3}{4}$ m
c, 5kg 250g = 5kg + $\frac{250}{100}$ kg = 5kg + $\frac{1}{4}$ kg = 5$\frac{1}{4}$ kg
Bài này 10 điểm ít nhưng mk vẫn đã làm giúp bạn ngay , mong bạn cho mk ctlhn nhé !! ( Nếu đc )
