Question

Tính bằng cách thuận tiện nhất 

A) 13/21 + 3 + 29/21

B) 3/4 + 3/5 + 2/8 + 4/10

 

Answer 1

\(\frac{13}{21}+3+\frac{29}{21}\)

\(=\frac{42}{21}+3\)

\(=2+3\)

\(=5\)

\(\frac{3}{4}+\frac{3}{5}+\frac{2}{8}+\frac{4}{10}\)

\(=\frac{3}{4}+\frac{3}{5}+\frac{1}{4}+\frac{2}{5}\)

\(=1+1\)

\(=2\)

Answer 2

a/(13/21 + 29/21) +3=42/21 +3 =2+3=5

b/ 3/4 + 3/5 +1/4 +2/5=(3/4+1/4)+(4/5+1/5)=1+1=2

Answer 3

lấy mt ra là xong

Answer 4

A) \(\frac{13}{21}\)+   3  +\(\frac{29}{21}\)

=\(\frac{42}{21}\)+   3

=   2  +   3

=    5

B)   \(\frac{3}{4}+\)\(\frac{3}{5}\)+\(\frac{2}{8}\)+\(\frac{4}{10}\)

=\(\frac{3}{4}\)+\(\frac{3}{5}\)+\(\frac{1}{4}\)+\(\frac{2}{5}\)

=(\(\frac{3}{4}\)+\(\frac{1}{4}\))+(\(\frac{3}{5}\)+\(\frac{2}{5}\))

=       1              +            1

=         2