1. Wang Ying read a book. On the first day, he read110 of this book. The next day, he read 16 more pages than the first day. At this time, the ratio of read pages to remaining pages is 1:3. How many pages are there in this book?

1/( 1+3)- 1/ 10- 10 = 1/20 16/( 1/20

2. Make a cuboid from a cube whose four sides are 4cm long. The surface area of this cuboid is at least 256 square centimeters and at most 272 square centimeters.

3. The perimeter ratio of two circles is 3:2, the difference of areas is 10 cm2, and the sum of the areas of two circles is (26) cm2.