TL

1/5 + 7/9 = 9/45 + 35/45 = 44/45

HT nha

T giúp mik

Tổng ban đầu của 2 phân số là:

        7/9 - 1/5 = 26/45

                    Đ/S: 26/45

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

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các số tiếp là 25, 36, 49, 64...

Gọi stn cần tìm là a ( \(a\in N\))

Ta có \(\frac{13-a}{35+a}=\frac{3}{5}\)

\(\Rightarrow5\left(13-a\right)=3\left(35+a\right)\)

\(65-5a=105+3a\)

\(65=105+8a\)

\(8a=65-105\)

\(8a=-40\)

\(\Rightarrow a=-5\)(KTM)

Nếu đầu bài là số nguyên thì a=-5 nha

Còn là stn thì không có giá trị nào thoả mãn.

HT

Gọi stn cần tìm là a \(\left(a\in N\right)\)

Ta có : \(\frac{13+a}{35-a}=\frac{3}{5}\)

\(\Rightarrow5\left(13+a\right)=3\left(35-a\right)\)

\(65+5a=105-3a\)

\(65=105-8a\)

\(105-65=8a\)

\(40=8a\)

\(\Rightarrow a=5\)(TM)

Vậy stn cần tìm là a

HT

49,5 nhé

KB

(1+1+1+1+1+1+1+1+1+1)=10.10x10=100

tui tích cho bà đó tuyết anh

125 nha

5103

1600

5555 bn nhé

Kết bn đi

lấy máy tính cho nhanh

có thể thấy rằng tích trên là tích của \(75-17+1=59\) số có tận cùng là 7

mà cứ 4 số có tận cùng là 7 nhân với nhau sẽ có tận cùng là 1

và 59 chia 4 dư 3 nên tích trên sẽ có cùng số tận cùng với \(7\times7\times7=343\)

vậy tích trên có tân cùng là 3