Respuesta :
Answer: A book cost $2.00
Step-by-step explanation: Given the no of books purchased by
Alana =4 Petra =2 Angus = 16
So
The total price of 4 books of Alana =4x$
Total price for Petra = 2x$
Total price of Alana and Petra =4x+2x
=6x$
Total price for Angus = 16x$
But given Angus received a discount of $15
So price post discount = 16x- 15
According to the question
16x-15 = 6x +5
Adding 15 both sides
16x +15-15 = 6x + 5+15
16x= 6x+20
Subtracting 6x both sides
16x - 6x = 6x - 6x + 20
10x = 20
i.e x=2
Cost of one book = $2