Question

[Hồ Văn Duy]

a,4/9 + 12/13 + 10/18 + 1/13

b,15/11 × 4/19 + 4/19 × 3/11 - 7/11 × 4/19

Answer 1

[Bùi Mạnh Hải]

a, 4/9 + 12/13 + 10/18 + 1/13

=  (4/9 + 10/18) + (12/13 + 1/13)

=  1 + 1

= 2

b, 15/11 × 4/19 + 4/19 × 3/11 - 7/11 × 4/19

=  4/19 x (15/11 + 3/11 - 7/11)

= 4/19 x 1

= 4/19

Answer 2

[Đặng Văn Nhật Thịnh]

a) \(\dfrac{4}{9}+\dfrac{12}{13}+\dfrac{10}{18}+\dfrac{1}{13}\)

\(=\left(\dfrac{4}{9}+\dfrac{10}{18}\right)+\left(\dfrac{12}{13}+\dfrac{1}{13}\right)\)

\(=1+1=2\)

b) \(\dfrac{15}{11}.\dfrac{4}{19}+\dfrac{4}{19}.\dfrac{3}{11}-\dfrac{7}{11}.\dfrac{4}{19}\)

\(=\dfrac{4}{19}.\left(\dfrac{15}{11}+\dfrac{3}{11}-\dfrac{7}{11}\right)=\dfrac{4}{19}.1=\dfrac{4}{19}\)