Explanation : Perimeter of square = 20 cm
∴ 4 × Side = 20
Side = 20/4 = 5 cm
Now, Side of square = Width of rectangle
= 5 cm
and Length of rectangle = 2 × Width
= 2 × 5 = 10 cm
Now, Area of rectangle = Length × Breadth
= 10 × 5 = 50 cm2
Explanation : (B) Given, length, breadth and height of Box A are 20 cm, 18 cm and 15 cm respectively.
∴ Volume of Box A = Length × Breadth × Height
= (20 × 18 × 15) cm3
Similarly, Volume of Box B = (18 × 12 × 5) cm3
Now, required ratio
Explanation : (B) From the given options,
Option (A), Area of square of side 10 cm = Side2 = (10)2 = 100 cm2
Now, are of rectangle of length 10 cm and breadth of 0.1 m or 10 cm. = 10 × 10 = 100 cm2 (true)
Option (B), 1 m 5 cm = 1.50m ≠ 1.5 m (false)
Option (C), 0.40 is same as 0.4, as zero after decimal value is irrelevent. (true)
Option (D), On dividing 3 by 4, we get 0.75
∴ ₹3/4 = ₹0.75 (true)