Exercise 2.4
1. Find:
2.Find the area of rectangle whose length is 5.7 cm and breadth is 3 cm
Solution:
We use the formula for area of the rectangle and concept of decimals to solve the question.
Length of rectangle =
Breadth of rectangle =
Thus, Area of rectangle = Length × Breadth = 5.7 × 3 =
Thus, the area of rectangle is
3.Find:
(i)-(iv)
(i) 1.3 × 10 =
(ii) 36.8 × 10 =
(iii) 153.7 × 10 =
(iv) 168.07 × 10 =
(v)-(viii)
(v) 31.1 × 100 =
(vi) 156.1 × 100 =
(vii) 3.62 × 100 =
(viii) 43.07 × 100 =
(ix)-(xii)
(ix) 0.5 × 10 =
(x) 0.08 × 10 =
(xi) 0.9 × 100 =
(xii) 0.03 × 1000 =
4.A two-wheeler covers a distance of 55.3 km in one litre of petrol. How much distance will it cover in 10 litres of petrol?
Solution:
By using Unitary Method, we can simply
Distance covered by two-wheeler in 1 litre of petrol = 55.3 km
Distance covered using 10 liters of petrol = 55.3 × 10 =
Therefore, it will cover a distance of 553.0 km in 10 liters of petrol.
5.Find:
(i)-(v)
(i) 2.5 × 0.3 =
=
=
(ii) 0.1 × 51.7 =
=
=
(iii) 0.2 × 316.8 =
=
=
(iv) 1.3 × 3.1 =
=
=
(v) 0.5 × 0.05 =
=
=
(vi)-(x)
(vi) 11.2 × 0.15 =
=
=
(vii) 1.07 × 0.02 =
=
=
(viii) 10.05 × 1.05 =
=
=
(ix) 101.01 × 0.01 =
=
=
(x) 100.01 × 1.1 =
=
=