Answer:
a. 
 15
15
b. 14

Explanation:
Given: Buying price of two ticket = 
 90
90
 Face value of each ticket = 
 52.5
52.5
∴ Face value of two ticket is 

= 
 105
105 
Now, to find markdown:
Markdown = Face value - Buying value
∴ Markdown = 

= 
 15 is the markdown.
15 is the markdown.
b. To find the percent markdown:

= 14.28 %
∴ Markdown percent is rounded to nearest whole number 14%