Question

tính bằng hai cách : 

a)12/17 : 17/12 + 5/7 :17/12

Answer 1

a) 12/17 : 17/12 + 5/7 : 17/12

= (12/17 + 5/7) : 17/12

= 1 : 17/12

= 12/17

Answer 2

Bài làm

Cách 1 :\(\frac{12}{17}:\frac{17}{12}+\frac{5}{7}:\frac{17}{12}\)

= \(\frac{12}{17}.\frac{12}{17}+\frac{5}{7}.\frac{12}{17}\)

= \(\frac{12}{17}.\left(\frac{12}{17}+\frac{5}{7}\right)\)

= \(\frac{12}{17}.\frac{169}{119}\)

= \(\frac{2028}{2023}\)

Cách 2 : \(\frac{12}{17}:\frac{17}{12}+\frac{5}{7}:\frac{17}{12}\)

= \(\frac{144}{289}+\frac{60}{119}\)

= \(\frac{2028}{2023}\)

Answer 3

1. 12/17:17/12+5/7:17/12=144/289+60/119=2028/2023

2.12/17:17/12+5/7:17/12=(12/17+5/7):17/12=169/119:17/12=2028/2023

Chúc bn học giỏi

kb nhé châm