From statement I: If no discount is given on the marked price of book, then the profit earned is Rs.60 more than the actual profit. Actual profit earned on selling the book is 20%.
Actual profit% = ((SP - CP)/CP) * 100 = 20
SP = (6/5) * CP
From statement II: Cost price of the book is Rs.200.
CP = 200
From statement I and II:
SP = 200 * 6/5 = 240
Then, profit earned when no discount is given = (240 - 200) + 60 = 100
Then, MP = New SP = CP + new profit = 200 + 100 = Rs.300
Hence, both statements I and II together are sufficient to find the answer.