# The length of the rectangular parallelepiped is 4.5. The width is 20% of the length and 3/10

**The length of the rectangular parallelepiped is 4.5. The width is 20% of the length and 3/10 of the height. Find the volume of a rectangular parallelepiped and its surface area**

The width is 20% of the length, that is, 20% of 4.5. Converting percentages to decimal numbers: 20% = 0.2. To find the fraction of a number, you need to multiply the number by the fraction: 4.5 * 0.2 = 0.9. This means the width is 0.9.

The width is 3/10 of the height. That is, 0.9 is 3/10 of the height. Hence, the height is 0.9: 3 * 10 = 3.

The volume of a parallelepiped is calculated by the formula V = a * b * h:

V = 4.5 * 0.9 * 3 = 12.15.

Surface area is the area of three pairs of equal rectangles:

Sp.p = 2 * (4.5 * 9) + 2 * (0.9 * 3) + 2 * (4.5 * 3) = 81 + 5.4 + 27 = 113.4.