1 .78 fen kg means "1" with (1) kg as the unit, divided into eight parts on average, with (7) parts taken; It also means "1" in the unit of (8) kg, with an average of 8 copies and (7) copies.

The two cylinders are equal in height and the volume sum is 48 cubic decimeters. The volume of a cone is (12) cubic decimeter.

3. If the heights of two cylinders are equal and the ratio of bottom radii is 1:3, the volume ratio of the two cylinders is (1:9). If the bottom radii of two cylinders are equal and the height ratio is 1: 3, then their volume ratio is (1: 3).

4. The ratio of the height of the bottom of the isosceles triangle to the height of the bottom is 8: 3. After cutting off the height of its fundus and splicing it into a rectangle, the area of the rectangle is 48 square centimeters, and the circumference of the rectangle is (56) centimeters.

5. Draw a plot of land with a length of 90 meters and a width of 60 meters in the scale of 65,438+0: (45,000,000) on the plan, with a length of exactly 20 cm and a width of (1313) cm.

6. It is known that A=2*2*3*M and B=2*N*3. If the greatest common divisor of A and B is 12 and the least common multiple is 60, then M = (5) and N = (2).

7. The surface area of a rectangle is 250 square centimeters, and the upper and lower sides are squares. If it can be cut into two squares with the same volume, the surface area will be increased by (50) square centimeters.