1、During a sale, the price of a book is reduced（减少）by 25%. The sale price is then further（进一步地）reduced by 40%. The cost of the book as a percentage（百分率） of the original（原来的）price is（ ）2、a/b is a fraction（分数）. If 2 is added to the numerator（分子）, the value of the fraction is 1/2. If 3 is added to the denominator（分母）, the fraction has a value of 1/3. The value of the sum a2 + b2 is ( )3、The floor of a fraction is defined（下定义）to be the largest integer（整数）which is not greater than t
