In this chapter, students learn different types of units for the measurement of area. For example, the total amount of surface covered by a planar figure is referred to as its area. Usually, its unit is square centimetres (cm2) or square meters (m2), etc. But additionally, the area can be measured in many different units, such as square decimetre, square millimetre (mm2), hectare (ha), and square kilometre (km2).
In RD Sharma Solutions for Class 7 Maths Chapter 20 mensuration 1, students study various topics such as perimeter and area of squares and rectangles. For example, the perimeter of a rectangle is the length of the boundary of a closed figure. A section of the plane enclosed by a simple closed figure is known as a plane region, while the measurement of the plane region enclosed is called its area.
The following are the formulae,
The perimeter of rectangle = 2 (l + b)
Area of rectangle = l * b
Another concept discussed in this chapter is the area between rectangles, where students are taught the techniques used to measure the distance between two or more rectangles. Moreover, topics such as areas of parallelogram and rhombus are also taught. The area of a parallelogram or a rhombus is defined as the region bounded by the sides of that parallelogram or a rhombus in a specified two-dimensional space.
Area of parallelogram = h* b square units
Area of rhombus = d1* d22
Furthermore, the triangle area is defined as the entire region enclosed by the three sides of any given triangle. This is equal to half of the base times height multiplied by breadth. Area of triangle = ½ * h * b square units.