Question

Find the missing values for the following:

S. No.	Length	Breadth	Area	Perimeter
(i)	12 m	8 m
(ii)	15 cm		90 sq.cm
(ii)		50 mm		300 mm
(iv)	12 cm			44 cm

Answer 1

(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

S. No.	Length	Breadth	Area	Perimeter
(i)	12 m	8 m	96 m2	40 m
(ii)	15 cm	6 cm	90 sq.cm	42 cm
(ii)	100 mm	50 mm	5000 sq. m	300 mm
(iv)	12 cm	10 cm	120 cm2	44 cm