FINDING THE AREA AND VOLUME OF A GIVEN SHAPE

Finding the area of a given shape is also done with the use of formulas. It’s no more difficult than what we have already been doing. In some ways, finding the area is easier than finding the perimeter. Most anyone in the trades knows how to find the square footage of a room. When you multiply the length of the room by the width of the room, you arrive at the square footage (Fig. 1.17). Well, this is exactly how you find the area of a rectan­gle or a square. There is no mystery or trick. Just multiply the length by the width for a rectangle or multiply one side by another side for a square, and you will have the area of the shape. To find the volume of a rectangle, you simply multiply the length by the width by the height. Different formulas are needed to find the area of trapezoids and triangles (Fig. 1.18 and

(тс) by 9 inches by 9 inches. This would advance up to multiplying 3.1416 by 81 square inches (9 X 9 = 81). The area of the circle would turn out to be 254.47 square inches. If you are looking for the volume of a cube, you simply multiply the three sides, as is illustrated in Figure 1.21. For a trape­zoidal prism, the volume is found by using the formula in Figure 1.22.

The math that is used in plumbing and pipe fitting is not very difficult to understand if you will accept the fact that it is necessary and that you need to understand it. What may appear daunting on the surface is actually pretty prac­tical in principle. With a combination of reference tables, a good calculator, and a little effort, you can accomplish your needs for math within the trade quickly.