M4maths Previous Puzzles

05 Apr 2012 book and notebook

Total cost of 4 books and 3 notebooks is 150 rupee. If cost of note book is more than that of book. Then possible number of ordered pair for the cost of note book and book will be
Given that the cost of note book is a multiple of 5 rupee and cost of book is more than 5 rupee.

OPtion

1) 1
2) 2
3) 3
4) 4
5) 5
6) 6
7) 7
8) 8
9) 9
10) more than 9

Solution

possible cost of note book = 25, 30, 35, 40

Correct Option: 4 Best Solution (9)

Dr.Dipin Singh   13 years AGO

possible pairs of cost of Note book and book are
Rs. 25 and Rs. 18.75
30 and 15
35 and 11.25
40 and 7.5

Like? Yes (6) | No (2)  

dineshv   13 years AGO

let cost of notebooks = N,cost of books = B
From given condition
4B + 3N = 150,
N>B,
N=5*X,B=5+Y
for the above coditions to satisfy the value of N starts from 25
There fore the values of N would be 25,30,35,40.
and values of B correspondigly would be 75/4,15,45/4,30/4

Like? Yes (5) | No (4)  

sajal jain   13 years AGO

suppose cost of one book = x
and cost of one note book = y

so,
4x + 3y = 150
but y>x and y=5*m , x = 5+n
4x=150-3y
4x=150-15*m
x = 15(10-m)/4
m can be 0,1,2,3,4,5,6,7,8,9
but at 9 x will be less then 5
and at 0,1,2,3,4 y will be less then x
so number of ordered pair for the cost of note book and book will be 4 (when m = 5,6,7,8)

Like? Yes (2) | No (3)  

Viru Sihag   13 years AGO

Let the cost of book is 5+y and cost of notebook is 5x. 4(5+y)+15x=150
then hit and trial method.

Like? Yes (2) | No (4)  

Datla Kanthi   13 years AGO

Possible values of book and notebook are
(18.75,25),
(15,30),
(11.25,35),
(7.5,40) so 4 pairs are possible

Like? Yes (1) | No (4)  

shiv vaishnav   13 years AGO

put cost of notebook = 5,10,15,20

Like? Yes (1) | No (4)  

Rakesh Kumar Kohli   13 years AGO

The possible ordered pairs for the cost of note book and book are (25,18.75),(30,15),(35,11.25),(40,7.50).
Thus possible number of ordered pair for the cst of note book and book will be 4.

Like? Yes (1) | No (4)  

Komal Jain   13 years AGO

Notebook cost is multiple of 5 and book cost is greater than 5.
And the expression is 4B+3N=150
for N=5 ... B > N same way for N=10,15,20
For N=25,B=18.75 .....(1)
For N=30,B=15 .....(2)
For N=35,B=11.25 .....(3)
For N=40,B=7.5 .....(4)
For greater values of N , B becomes less than 5
So therefore there are in all 4pairs
(N,B)={(25,18.75),(30,15),(35,11.25),(40,7.5)}

Like? Yes (1) | No (4)  

sridhar reddy   13 years AGO

notebook = n
book = b
4b+3n=150 & n>b & b>5 R.s
n is a multiple of 5
ordered pairs (notebook, book)
(25,18.75),(30,15),(35,11.25),(40,7.50) are 4

Like? Yes (1) | No (4)