Answer:
The price of 1 exercise book is $122.45.
Step-by-step explanation:
This question is solved using a system of equations.
I am going to say that:
x is the price of one exercise book.
y is the price of one textbook.
Total cost of 10 exercise books and 2 textbooks is $1400.00.
This means that:
[tex]10x + 2y = 1400[/tex]
Since we want x:
[tex]2y = 1400 - 10x[/tex]
[tex]y = 700 - 5x[/tex]
One also finds the total cost of 3 textbooks and 30 exercise books is $3000.
This means that:
[tex]3x + 30y = 3000[/tex]
Since [tex]y = 700 - 5x[/tex]
[tex]3x + 30(700 - 5x) = 3000[/tex]
[tex]3x + 21000 - 150x = 3000[/tex]
[tex]147x = 18000[/tex]
[tex]x = \frac{18000}{147}[/tex]
[tex]x = 122.45[/tex]
The price of 1 exercise book is $122.45.