Find the missing values for the following:S. No.LengthBreadthAreaPerim

Find the missing values for the following:S. No.LengthBreadthAreaPerimeter(i)12 m8 m(ii)15 cm90 sq.cm(ii)50 mm300 mm(iv)12 cm44 cm

Answer»

(i) Given length l = 12 m; Breadth b = 8 cm

∴ Area of rectangle = l x b sq. units = 12 x 8 m²

= 96 m²

Perimeter of the rectangle = 2 x (1 + b) units

= 2 x (12 + 8)m = 2 x 20 = 40m

(ii) Given Length l = 15 cm; Area of the rectangle = 90 sq. cm

l x b = 90; 15 x 6 = 90; b = \(\frac{90}{15}\) = 6 cm

Perimeter of the rectangle = 2 x (l + b) units = 2 x (15 + 6) cm = 2 x 21 cm

= 42 cm

(iii) Given Breadth of rectangle = 50 mm; Perimeter of the rectangle = 300 mm

2 x (l + b) = 300

2 x (l + 50) = 300

l + 50 = \(\frac{300}{2}\) = 150

l = 150 – 50

l = 100

Area = l x b sq. untis = 100 x 50 mm² = 5000 mm²

(iv) Length of the rectangle = 12 cm; Perimeter = 44 cm

2(l + b) = 44

2(12 + b) = 44

12 + b = \(\frac{44}{2}\)

12 + b = 22; b = 22 – 12; b = 10 cm

Area = l x b sq. units

= 12 x 10 cm² = 120 cm²