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Sub-Topic (Example: name of college)
VIT
Mensuration
Rectangle :
 Area = lb
 Perimeter = 2(l+b)
Square :
 Area = a×a
 Perimeter = 4a
Parallelogram:
 Area = l × h
 Perimeter = 2(l+b)
Mensuration
Triangle :
Area =b×h/2 or √s(s-a)(s-b)(s-c)…………….where
s=a+b+c/2
Right angle Triangle :
 Area =1/2(bh)
 Perimeter = b+h+d
Isosceles right angle triangle :
 Area = ½. a2
 Perimeter = 2a+d………where d=a√2
IMPORTANT FORMULAE:
Equilateral Triangle :
 Area = √3. a2/4 or ½(ah)….where h = √3/2
 Perimeter = 3a
Trapezium :
 Area = 1/2h(a+b)
 Perimeter = Sum of all sides
Rhombus :
 Area = d1 × d2/2
 Perimeter = 4l
Mensuration
Quadrilateral:
Area =1/2 × Diagonal × (Sum of offsets)
Circle :
 Area = πr^2 or πd^2/4
 Circumference = 2πr or πd
 Area of sector of a circle = (θπr^2 )/360
Sphere:
 Volume: V = 4/3 πr3
 Surface Area: S = 4πr2
Mensuration
Hemisphere :
 Volume = 2/3 π r3
 Curved surface area(CSA) = 2 π r2
 Total surface area = TSA = 3 π r2
Right Circular Cylinder :
 Volume of Cylinder = π r2 h
 Lateral Surface Area (LSA or CSA) = 2π r h
 Total Surface Area = TSA = 2 π r (r + h)
 Volume of hollow cylinder = π r h(R2 – r2)
Right Circular cone :
 Volume = 1/3 π r2h
 Curved surface area: CSA= π r l
 Total surface area = TSA = πr(r + l )
Mensuration
Some other Formula :
 Area of Pathway running across the middle of a rectangle =
w(l+b-w)
 Perimeter of Pathway around a rectangle field = 2(l+b+4w)
 Area of Pathway around a rectangle field =2w(l+b+2w)
 Perimeter of Pathway inside a rectangle field =2(l+b-4w)
 Area of Pathway inside a rectangle field =2w(l+b-2w)
 Area of four walls = 2h(l+b)
Mensuration
If area of square field is 6.76 hectare, then its length is __________ m.
A)
B)
C)
D)
260
275
290
315
Question 1
Let the diameter be 14 cm and height be 6 cm. Find the volume of cylinder
and cone. (in cm3)
A)
B)
C)
D)
800,400
924,308
1024,484
None of these
Question 2
How many cubes of 10 cm edge can be put in a cubical box of 1 m edge?
A)
B)
C)
D)
10
50
100
1000
Question 3
The area of a rectangular ground is 12500 m2. If its length is 125 m, then its
perimeter is(in m)
A)
B)
C)
D)
450
500
575
625
Question 4
In a triangle PQR, PQ = QR = 10 cm, PR = 12 cm. QS is drawn
perpendicular to PR where s is on the line PR. Find the length of QS.(in cm)
A)
B)
C)
D)
8
10
12.5
None of these
Question 5
A triangle is made from a rope. The sides of triangle are 21 cm, 15 cm and
32 cm. What will be the area of the square made from the rope?(in cm2)
A)
B)
C)
D)
289
324
400
456
Question 6
The surface area of a cube whose volume is 64, is _____.
A)
B)
C)
D)
32
64
96
108
Question 7
Volume of a sphere whose surface area is 144π cm2 (in cm3), is ________.
A)
B)
C)
D)
256π
288π
325
None of these
Question 8
The length, width and height of a rectangular solid are in the ratios 5 : 4 : 2.
If total surface area is 4864m2, then height of the solid is _____________.
A)
B)
C)
D)
16
20
24
28
Question 9
Length of cloth in meters which is 2.5 m wide is required to make a conical
tent with base radius of 7 m and height of 24 m is _________.
A)
B)
C)
D)
90π
110π
125π
140π
Question 10
The base of a rectangular tank is 12 feet long and 8 feet wide, and height of
the tank is 30 inches. If water is pouring into the tank at the rate of 2 cubic
feet per second, then time taken required to fill the tank is _______.
A)
B)
C)
D)
1 min
2 min
5 min
7 min
Question 11
A rectangular container with dimensions 4 inches, 9 inches, 10 inches is
kept into a cylindrical container with a diameter of 6 inches. Assuring the
milk does not overflow the container, find the height(in inches)to which the
milk will reach high?
A)
B)
C)
D)
15/π
25
30/π
40/π
Question 12
Ratio of the total surface area to the lateral surface area of a cylinder with
base radius 60 cm and height 40 cm is ______.
A)
B)
C)
D)
2:3
5:2
6:7
None of these
Question 13
The diameter of a copper sphere is 12 cm. The sphere is melted and drawn
into a long wire of uniform circular cross section. If length of the wire is 72
cm, then radius of wire is _________ cm.
A)
B)
C)
D)
4
3
2
None of these
Question 14
A spherical ball, 12 cm in diameter, is melted and cast into a conical mould,
the base of which is 24 cm in diameter. What is the height of the cone?( in
cm)
A)
B)
C)
D)
6
12
15
None of these
Question 15
THANK YOU

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Mensuration.pptx

  • 1.
  • 4. Rectangle :  Area = lb  Perimeter = 2(l+b) Square :  Area = a×a  Perimeter = 4a Parallelogram:  Area = l × h  Perimeter = 2(l+b) Mensuration Triangle : Area =b×h/2 or √s(s-a)(s-b)(s-c)…………….where s=a+b+c/2 Right angle Triangle :  Area =1/2(bh)  Perimeter = b+h+d Isosceles right angle triangle :  Area = ½. a2  Perimeter = 2a+d………where d=a√2 IMPORTANT FORMULAE:
  • 5. Equilateral Triangle :  Area = √3. a2/4 or ½(ah)….where h = √3/2  Perimeter = 3a Trapezium :  Area = 1/2h(a+b)  Perimeter = Sum of all sides Rhombus :  Area = d1 × d2/2  Perimeter = 4l Mensuration
  • 6. Quadrilateral: Area =1/2 × Diagonal × (Sum of offsets) Circle :  Area = πr^2 or πd^2/4  Circumference = 2πr or πd  Area of sector of a circle = (θπr^2 )/360 Sphere:  Volume: V = 4/3 πr3  Surface Area: S = 4πr2 Mensuration
  • 7. Hemisphere :  Volume = 2/3 π r3  Curved surface area(CSA) = 2 π r2  Total surface area = TSA = 3 π r2 Right Circular Cylinder :  Volume of Cylinder = π r2 h  Lateral Surface Area (LSA or CSA) = 2π r h  Total Surface Area = TSA = 2 π r (r + h)  Volume of hollow cylinder = π r h(R2 – r2) Right Circular cone :  Volume = 1/3 π r2h  Curved surface area: CSA= π r l  Total surface area = TSA = πr(r + l ) Mensuration
  • 8. Some other Formula :  Area of Pathway running across the middle of a rectangle = w(l+b-w)  Perimeter of Pathway around a rectangle field = 2(l+b+4w)  Area of Pathway around a rectangle field =2w(l+b+2w)  Perimeter of Pathway inside a rectangle field =2(l+b-4w)  Area of Pathway inside a rectangle field =2w(l+b-2w)  Area of four walls = 2h(l+b) Mensuration
  • 9. If area of square field is 6.76 hectare, then its length is __________ m. A) B) C) D) 260 275 290 315 Question 1
  • 10. Let the diameter be 14 cm and height be 6 cm. Find the volume of cylinder and cone. (in cm3) A) B) C) D) 800,400 924,308 1024,484 None of these Question 2
  • 11. How many cubes of 10 cm edge can be put in a cubical box of 1 m edge? A) B) C) D) 10 50 100 1000 Question 3
  • 12. The area of a rectangular ground is 12500 m2. If its length is 125 m, then its perimeter is(in m) A) B) C) D) 450 500 575 625 Question 4
  • 13. In a triangle PQR, PQ = QR = 10 cm, PR = 12 cm. QS is drawn perpendicular to PR where s is on the line PR. Find the length of QS.(in cm) A) B) C) D) 8 10 12.5 None of these Question 5
  • 14. A triangle is made from a rope. The sides of triangle are 21 cm, 15 cm and 32 cm. What will be the area of the square made from the rope?(in cm2) A) B) C) D) 289 324 400 456 Question 6
  • 15. The surface area of a cube whose volume is 64, is _____. A) B) C) D) 32 64 96 108 Question 7
  • 16. Volume of a sphere whose surface area is 144π cm2 (in cm3), is ________. A) B) C) D) 256π 288π 325 None of these Question 8
  • 17. The length, width and height of a rectangular solid are in the ratios 5 : 4 : 2. If total surface area is 4864m2, then height of the solid is _____________. A) B) C) D) 16 20 24 28 Question 9
  • 18. Length of cloth in meters which is 2.5 m wide is required to make a conical tent with base radius of 7 m and height of 24 m is _________. A) B) C) D) 90π 110π 125π 140π Question 10
  • 19. The base of a rectangular tank is 12 feet long and 8 feet wide, and height of the tank is 30 inches. If water is pouring into the tank at the rate of 2 cubic feet per second, then time taken required to fill the tank is _______. A) B) C) D) 1 min 2 min 5 min 7 min Question 11
  • 20. A rectangular container with dimensions 4 inches, 9 inches, 10 inches is kept into a cylindrical container with a diameter of 6 inches. Assuring the milk does not overflow the container, find the height(in inches)to which the milk will reach high? A) B) C) D) 15/π 25 30/π 40/π Question 12
  • 21. Ratio of the total surface area to the lateral surface area of a cylinder with base radius 60 cm and height 40 cm is ______. A) B) C) D) 2:3 5:2 6:7 None of these Question 13
  • 22. The diameter of a copper sphere is 12 cm. The sphere is melted and drawn into a long wire of uniform circular cross section. If length of the wire is 72 cm, then radius of wire is _________ cm. A) B) C) D) 4 3 2 None of these Question 14
  • 23. A spherical ball, 12 cm in diameter, is melted and cast into a conical mould, the base of which is 24 cm in diameter. What is the height of the cone?( in cm) A) B) C) D) 6 12 15 None of these Question 15

Editor's Notes

  1. Answer: A A = a² = 6.76 Ha = 67600m² (1 Ha = 10000 m²) Therefore, a = √67600 = 260 m
  2. Answer: B Given, Diameter = 14 cm => r = 7 cm h = 6 cm Volume of cylinder = πr2h = (22/7)*7*7*6 = 924 cm3 Volume of cone = 1/3πr2h = 1/3*22/7*7*7*6 = 308 cm3.
  3. Answer: D Number of cubes = (100*100*100) / (10*10*10)         (1 m = 100 cm) = 1000
  4. Answer: A We know l*b = A Therefore, 125*b = 12500 b = 100 Therefore, P = 2(l + b) = 2(125 + 100) = 450 m
  5. Answer: A Image: View->Notes page PQ = QR PS = SR = 6 cm In right angle triangle PQS, By Pythagoras theorem, 10² = x² - 6² x² = 64 cm x = 8 cm
  6. Answer: A Image: View->Notes page Perimeter of triangle = 15 + 21 + 32 = 68 cm Now, perimeter of triangle = perimeter of square (Since the rope is made as a square) Therefore, Perimeter of square = 4a = 68 => a = 68/4 = 17 cm Therefore, Area of the square = a2 = 172 = 289 cm2
  7. Answer: C Volume of a cube = 64 But , volume of cube = (edge)3 64 = (edge)3 => (4)3 = (edge)3 Taking cube root on both sides, edge of cube = 4 Now, length of the edge = 4 As, cube has 6 edges, therefore Surface area of a cube = 6(edge)2 = 6 (4)2 = 6(16) = 96
  8. Answer: B Surface area of a sphere = 144π cm2 Now, surface area of a sphere with radius r can be given by Surface area of a sphere = 4π r2 144π = 4π r2 r2 = 36 r = 6 Therefore, volume of given sphere = 4π/3 (radius)3 = 4π/3 (6)3 = 288 π cm3
  9. Answer: A Length, width and height of a rectangular solid are in the ratios 5 : 4 : 2. Let Length, width and height be 5x, 4x and 2x respectively. Now, surface area of a rectangular solid of length (l), width (b) and height (h) = 2(lb + bh + hl) Therefore, 4864 = 2(5x*4x + 4x*2x + 2x*5x) = 2(20x2 + 8x2 + 10x2) = 2(38x2) => 4864 = 76x2 x2 = 4864/76 = 64 x = 8 Therefore, height of the rectangular solid = 2(8) = 16
  10. Answer: D Here, area of the cloth will be equal to curved surface of the cone Now, for finding curved surface of a cone, first we have to find slant height of the cone. Slant height of a cone, l = √(height)2 + (radius)2 = √(24)2 + (7)2 = √576 + 49 = √625 = 25 m Therefore, A = 2πrl = 2π * 7 * 25 = 350π Area of cloth = 350π L * 2.5 = 350π l = 140π
  11. Answer: B Given that base of a rectangular tank is 12 feet long and 8 feet wide. Now, height of the tank = 30 inches = 30/12 = 2.5 feet. Volume of the tank = l*b*h = 12*8*2.5 = 240 cubic feet Now, it is given that water is pouring at rate of 2 cubic feet per second. Therefore, time taken to fill the tank = 240/2 = 120 seconds = 2 minute
  12. Answer: D Volume of a rectangular container = l*b*h = 4*9*10 = 360 cube inches. Volume of the milk in the cylinder = 360 cube inches. Volume of the cylindrical container = πr2h πr2h = 360 Now, diameter of the container is given 6 inches. Radius of container = 6/2 = 3 inches Therefore, π(3)2h = 360 9πh = 360 h = 360/9π = 40/π
  13. Answer: B Given cylinder has a base radius of 60 cm and height 40 cm. i.e. r = 60 and h = 40 Now, lateral surface area = 2πrh = 2π*60*40 = 4800π Total surface area = Lateral surface + 2* Base area = (2πrh) + (2*πr2) = (4800π) + (2*π (60)2) = 4800π + 7200π = 12000π Total surface area:lateral area = 12000π:4800π = 5/2 i.e. Total surface area : Lateral surface area = 5 : 2
  14. Answer: C Diameter of the sphere = 12 cm Therefore, radius of sphere = d/2 = 12/2 = 6 Volume of the sphere = 4/3 πr3 = 4/3 π(6)3 = 288π Now, sphere is melted and transformed into a wire. Hence, volume of the sphere is converted to volume of wire Volume of wire = Volume of sphere = 288π Now, wire can be thought of as a thin cylinder with long height = 72 cm Volume of wire = πr2h But, height h = 36 π*r2*72 = 288π r2 = 4 r = 2 cm
  15. Answer: A Here, spherical ball is melted and cast into a cone. Hence, we can say that volume of the ball and cone remains the same. It is given that diameter of the ball is 12 cm. Therefore, its radius = 12/2 = 6 cm Again, diameter of the new cone is 24 cm Therefore, its radius = 24/2 = 12 cm Let h be the height of the cone. Now, volumes of the spherical ball and conical mould are same. 4/3πr3 = 1/3πr2h 4/3*π*(6)3 = 1/3*π*(12)2*h h = 4/3*π*(6)3 / 1/3*π*(12)2 h = 288/48 = 6 cm