\(\frac{7}{12}=\frac{1}{3}+\frac{1}{4}\) k nha

\(\frac{7}{12}=\frac{1}{3}+\frac{1}{4}\)

7/8=1/2+1/4+1/8

\(\frac{7}{8}=\frac{1}{8}+\frac{2}{8}+\frac{4}{8}=\frac{1}{8}+\frac{1}{4}\)\(+\frac{1}{2}\)

1/3=1/12+1/4

Các phân số thỏa mãn:1/9,2/8,3/7,4/6

Ta có:\(\frac{7}{8}=\frac{1}{8}+\frac{2}{8}+\frac{4}{8}=\frac{1}{8}+\frac{1}{4}+\frac{1}{2}\)

Vậy \(\frac{7}{8}=\frac{1}{2}+\frac{1}{4}+\frac{1}{8}\)

Trả lời:7/8=1/2+1/4+1/8

1/5= 1/15 + 1/10 + 1/30

13/35=1/5+1/7+1/35           17/63=1/7+1/9+1/63

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Bài 1:

Giải:

Số tự nhiên lớn nhất có hai chữ số là 99

Vì 99 : 36 = 2 dư 27

Vậy số tự nhiên lớn nhất có 2 chữ số chia hết cho 36 là:

99 - 27 = 72

Các phân số thỏa mãn đề bài là:

\(\frac{15}{36}\) = \(\frac{15\times2}{36\times2}=\) \(\frac{30}{72}\)

Bài 2:

Tử số bằng 5/7 mẫu số

4812 ứng với:

1+ 5/7 = 12/7 (mẫu số)

Mẫu số là:

4812 : 12/7 = 2807

Tử số là:

4812 - 2807 = 2005

Phân số cần tìm là:

2005/2807