LI – Mensuration
1. The area of a rhombus is 16 cm2
and the length of one of its diagonal is 4 cm. Calculate the length
of other the diagonal. 2
2. The parallel sides of a trapezium measure 12 cm and 20 cm. Calculate its area if the distance
between the parallel lines is 15 cm. 2
3. Calculate the height of a cuboid which has a base area of 180 cm2
and volume is 900 cm3
. 3
4. A lawnmower takes 750 complete revolutions to cut grass on a field. Calculate the area of the field
if the diameter of the lawnmower is 84 cm and length is 1 m.
Answers
Answer:
1. 8 cm
2. 240 cm^2
3. 5 cm
4. 1980 cm^2
Step-by-step explanation:
1. Area of Rhombus = 1/2 × D1 × D2
16cm^2 = 4cm × D2
16/2 = D2
8 cm = other diagonal
2. Area of Trapezium = 1/2 × (P1 + P2) × h
Area of Trapezium = 1/2 × (12 + 20) × 15
Area of Trapezium = 1/2 × 32 × 15
Area of Trapezium = 1/2 × 480
Area of Trapezium = 240 cm^2
3. Volume of Cubiod = l × b × h
900 cm^3 = 180 × h
900/180 = h
5 cm = height
4. length of lawnmower = 1m = 100cm
Its circumference = π × D = 22/7 × 84 = 264 cm
Length of field will be = 264 × 750 = 198000 cm
Here, the width of field = length of the lawnmower i.e. 100 cm
So, area of field = 198000 × 100 = 19,800,000 cm²
= 1980 m²
Hope it helps!!
Step-by-step explanation:
1. area of rhombus :-1/2×d1×d2
=)1/2×d1×4=16
=)1/2xd1=4
=)d1=8
2. area of trapezium = 1\2 * (12 Cm + 20 cm) *15 cm
= 11 * 15
= 165
3. Volume of cuboid = Base area × height
Given, Volume = 900 cm³ and Base area = 180 cm²
=> Height = 900 ÷ 180 cm = 5 cm
4.Given, length of lawnmower = 1m = 100cm
Its circumference = π × D = 22/7 × 84 = 264 cm
Length of field will be = 264 × 750 = 198000 cm
Here, the width of field = length of the lawnmower i.e. 100 cm
So, area of field = 198000 × 100 = 19,800,000 cm²
Or, 1980 m²