bulb is selected at randullTSECTION-Dson,A shopkeeper buys a number of

1.	bulb is selected at randullTSECTION-Dson,A shopkeeper buys a number ofamount, each book would have cost him R 10 less. How many book23.books for 7800. If he had bought 4 more books for the satnezero.r lhat if a line is drawn parallelto one side of a triangle to intersectDuovnnints, then the other two sides are divided
Answer» Let the shopkeeper buy x number of books. According to the given condition, cost of x books = Rs. 80 Therefore cost of each book = Rs. 80/x Again, when he had bought 4 more books, then total number of books in this case = x + 4 So, cost of each book in this case = Rs. 80/x+4 According to the question, Cost of each book in first case - cost of each book in second case = 1 Rupee 80/x - 80/x+4 = 1 80(x+4) - 80x / x(x+4) = 1 x^2+ 20x - 16x - 320 = 0 (x - 16)(x + 20) = 0 x = 16 or x = -20 Hence, the shopkeeper bought 16 books.

bulb is selected at randullTSECTION-Dson,A shopkeeper buys a number ofamount, each book would have cost him R 10 less. How many book23.books for 7800. If he had bought 4 more books for the satnezero.r lhat if a line is drawn parallelto one side of a triangle to intersectDuovnnints, then the other two sides are divided

Answer»

Let the shopkeeper buy x number of books.

According to the given condition, cost of x books = Rs. 80

Therefore cost of each book = Rs. 80/x

Again, when he had bought 4 more books, then total number of books in this case = x + 4

So, cost of each book in this case = Rs. 80/x+4

According to the question,

Cost of each book in first case - cost of each book in second case = 1 Rupee

80/x - 80/x+4 = 1

80(x+4) - 80x / x(x+4) = 1

x^2+ 20x - 16x - 320 = 0

(x - 16)(x + 20) = 0

x = 16 or x = -20

Hence, the shopkeeper bought 16 books.