Solution: suppose this basket of apples turned out to be x kilograms.

3x/ 10+6 = 7/ 13(x-3x/ 10-6)

3x/ 10+60/ 10 = 7x/ 13-2 1x/ 130-42/ 13

60+3x/ 10 = 7x/ 13-2 1x/ 130-42/ 13

13(60+3x)/ 130 = 10(7x-42)/ 130-2 1x/ 130

39x+780=70x-420-2 1x

10x= 1200

x= 120

A: This basket of apples was originally 120kg.

(2) Let * * have X books.

x-(58+42)=60

Solution: x- 100=60

x= 160

Because 58 books are not story books, 160-58= 102 are science books and other books; 42 books are not science books, so160-42 =118 books are story books and other books;

Suppose there are Z books in other books.

1 18 z+ 102 z = 60

-2z = 60- 1 18- 102

-2z=- 160

Z=80 (so there are 80 other books)

1 18-80=38 (Ben)

Answer; 38 books on science and technology.

(3) setting; Party A and Party B are x kilometers apart.

(4) If the selling price is 140, you can earn 2/5, which is actually 140*2/5=56 yuan; So; Price tag; 140, profit: 56; Display profit = bid price-purchase price; So the purchase price = 140-56=84 yuan.

According to the meaning of the question: profit is; 120-84=36 yuan; 36/ 140=9/35

A: You can earn 9/35. (I don't know if it's right)