Question

Tính bằng cách thuận tiện nhất

3/5 + 6/11 + 7/13 + 2/5 + 16/11 + 19/13

Answer 1

Answer 2

\(\dfrac{3}{5}+\dfrac{6}{11}+\dfrac{7}{13}+\dfrac{2}{5}+\dfrac{16}{11}+\dfrac{19}{13}\\ =\left(\dfrac{3}{5}+\dfrac{2}{5}\right)+\left(\dfrac{6}{11}+\dfrac{16}{11}\right)+\left(\dfrac{7}{13}+\dfrac{19}{13}\right)\\ =\dfrac{5}{5}+\dfrac{22}{11}+\dfrac{26}{13}\\ =1+2+2\\ =5\)

Answer 3

5

Answer 4

(3/5+2/5)+(6/11+16/11)+(7/13+19/13)

=1+2+2=5

Answer 5

5

Answer 6

= ( 3/5 + 2/5 ) + (6/11 + 16/11) + (7/13 + 19/13)

=      5 + 2 + 2

= 7 + 2

= 9

Answer 7

= 5

Answer 8

= 5

Answer 9

= 5