Question

 Tính nhanh (\(\frac{12}{26}\)+\(\frac{5}{8}\)) + \(\frac{7}{13}\)

Answer 1

( 12/26 + 5/8 )  + 7/13

= 12/26 + 5/8 + 7/13

= 5/8 + 12/26 + 7/13

= 5/8 + 12/26 + 14/26

= 5/8 + 1

= 13/8

Answer 2

( \(\frac{12}{26}+\frac{5}{8}\) )+\(\frac{7}{13}\)

= \(\frac{6}{13}+\frac{5}{8}\)+\(\frac{7}{13}\)

=( \(\frac{6}{13}+\frac{7}{13}\))+ \(\frac{5}{8}\)

=1+\(\frac{5}{8}\)

=\(1\frac{5}{8}=\frac{13}{8}\)

Answer 3

Chỉnh lại :

( 12/26 + 7/13 ) + 5/8 = 1 + 5/8 = 13/8