A student bought some books for Rs.60. Had he bought 2 books less
same amount the cost of each book would have been 1 rupee more. Find
number of books bought by the student.
Answers
Answer:
A student bought some books for Rs.60. Had he bought 2 books less for the same amount the cost of each book would have been I rupee more. The number of books bought by the student is 12
Step-by-step explanation:
Let x be the cost of one book.
The number of books that can be bought by rs 60 at rs x each is given by:
Books = 60/x
When the price of a book is increased by 1 rupee, the cost becomes:
rs (x + 1)
Now, with rs 60 you can purchase:
60/(x + 1)
If the student buys at x + 1, he gets 2 books less. So, we write this as:
60/x = 60/(x + 1) + 2
60(x + 1) = 60x + 2(x + 1)x
60x + 60 = 60x + 2x² + x
Collecting the like terms together we have:
2x² + x - 60 = 0
Applying quadratic dormula we have:
x = [-1±√(1 + 4 × 60 × 2)]/4
x = 5.2 which is approximately 5
Therefore, the cost of each book is rs 5.
The student bought:
60/5 = 12 books.
Answer:12 books
Step-by-step explanation:
Let the no. Of books he bought be x.
Cost of each book=60/x.
A.T.Q.
60/x - 60/x-2=1
60x-120-60x/x²-2x=1
-120=x²-2x
x²-2x+120=0
x²+10x-12x+120=0
x(x+10)-12(x+10)=0
(x+10)(x-12)=0
Possible values of x=-10,12
Value of x=12
Cost of each book=60/12
=₹5