1. Tính
a)$\frac{-1}{3}$ +$\frac{7}{3}$
=$\frac{-1+7}{3}$
=$\frac{6}{3}$ = 2
b) $\frac{3}{5}$ +$\frac{-1}{3}$
=$\frac{9+(-5)}{15}$
=$\frac{4}{15}$
c)$\frac{-2}{13}$ +$\frac{-11}{26}$
=$\frac{-52+(-143)}{338}$
=$\frac{-195}{338}$ =$\frac{-15}{26}$
d) -2+$\frac{-5}{8}$
= $\frac{-2}{1}$ +$\frac{-5}{8}$
= $\frac{-16}{8}$ +$\frac{-5}{8}$
= $\frac{-16+(-5)}{8}$
= $\frac{-21}{8}$
e) $\frac{18}{24}$+ $\frac{35}{-10}$
= $\frac{3}{4}$+$\frac{-7}{2}$
=$\frac{3}{4}$+$\frac{-14}{4}$
=$\frac{3+(-14)}{4}$
= $\frac{-11}{4}$
2.
a)$\frac{3}{2}$+ $\frac{-3}{5}$+ $\frac{1}{4}$
=$\frac{30}{20}$+ $\frac{-12}{20}$+ $\frac{5}{20}$
= $\frac{30+(-12)+5}{20}$
= $\frac{23}{20}$
b)$\frac{2}{7}$+ $\frac{-1}{3}$+ $\frac{1}{27}$
=$\frac{6}{27}$+ $\frac{-7}{27}$+ $\frac{1}{27}$
= $\frac{6+(-7)+1}{27}$
= $\frac{0}{27}$
=0
2. Điền dấu thích hợp(<; >; =) vào chỗ chấm
a) > b) < c) >
Chúc bạn học tốt !!!
