2 Since the multiple of 2,3,5 is 30, that is, the least common multiple of 2,3,5 is 30, then all those that meet the requirements are 30n, so 30n >;: = 100, then n >; =3.3, so the minimum n is 4, so it is 120.
3, the minimum factor is 1, and the maximum is 36.
4 let this decimal be x,
Then from the topic 100x-x=25, so x=25/99.
53b
Let the length of a rectangle be x, then we can know that (X-4) 2 = X (X-4)-20, so x=9, that is, the area of the rectangle is 45.
7, the surface area is equal to the area of the original cuboid+the area increased by these two faces, and the maximum is formed when the two faces are 6*5.
2(6*5+6*4+4*5)+2*6*5=208
8.6 times
9 * * * has 1000 block, so the length is1000 * 0.1m =100m.
10, 18
1 1,30n,30