Question

Tính nhanh :

\(\dfrac{4}{7.25}+\dfrac{5}{25.10}+\dfrac{6}{10.36}+\dfrac{9}{36.15}\)

Answer 1

Gọi kết quả của phép tính là A

=> \(\dfrac{4}{7.25}\) + \(\dfrac{5}{25.10}\) + \(\dfrac{6}{10.36}\) + \(\dfrac{9}{36.15}\) = A

<=> \(\dfrac{4}{175}\) + \(\dfrac{5}{250}\) + \(\dfrac{6}{360}\) + \(\dfrac{9}{540}\) = A

<=> (\(\dfrac{4}{175}\) + \(\dfrac{1}{50}\)) + (\(\dfrac{1}{60}\) + \(\dfrac{1}{60}\)) = A

<=> (\(\dfrac{200}{8750}\) + \(\dfrac{175}{8750}\)) + \(\dfrac{2}{60}\) = A

<=> \(\dfrac{375}{8750}\) + \(\dfrac{1}{30}\) = A

<=> \(\dfrac{3}{70}\) + \(\dfrac{1}{30}\) = A

<=> \(\dfrac{90}{2100}\) + \(\dfrac{70}{2100}\) = A

<=> \(\dfrac{160}{2100}\)

Answer 2

Lỡ gửi trả lời còn nữa nè :

<=> \(\dfrac{160}{2100}\) = A

<=> A = \(\dfrac{8}{105}\)

Vậy tổng của biểu thức là \(\dfrac{8}{105}\)