Problem 1 :
The bottom of a tank measures 50 m × 40 m. Find its depth if it contains 4000 m³ of water.
Solution :
Length = 50 m, Breadth = 40 m, Volume = 4000 m³
Volume of rectangle = length × breadth × height
4000 = 50 ⋅ 40 ⋅ h
4000 = 2000 ⋅ h
h = 4000/2000
h = 2 m
So, depth of water tank is 2 m.
Problem 2 :
The volume of a rectangular prism whose length, breadth and height are 2a, 3a and 4a is.
a) 24a2 b) 24a3 c) 12a3 d) none of these
Solution :
Measures of rectangular prism,
Length = 2a, width = 3a and height = 4a
Volume of rectangular prism = length x width x height.
= 2a ⋅ 3a ⋅ 4a
= 24a3
Problem 3 :
The surface area of a cuboid is 1372 sq. cm. If its dimensions are in the ratio of 4 : 2 : 1, find the volume.
Solution :
Surface area of rectangular prism = 1372 sq.cm
length = 4x, width = 2x and height = x
2(4x ⋅ 2x + 2x ⋅ x + x ⋅ 4x) = 1372
2(8x2 + 2x2 + 4x2) = 1372
2(14x2) = 1372
x2 = 49
x = 7
Volume = 4x(2x)(x)
= 8x3
= 8(7)3
= 2744 cm3
Problem 4 :
The volume of a rectangular prism is 24 ft3, the height is 2, what are three possible measures for the length and width of the prism?
Solution :
Volume of rectangular prism = 24
length ⋅ width ⋅ height = 24
length ⋅ width ⋅ 2 = 24
length ⋅ width = 12
If length = 3, width = 4
If length = 2, width = 6
If length = 1, width = 12
Problem 5 :
A box of tissues has a length of 11.2 cm, a width of 11.2 cm and a height of 13 cm. What is the volume of the tissue box ?
Solution :
length = 11.2 cm, width = 11.2 cm and height = 13 cm
Volume of the box = length x width x height
= 11.2 x 11.2 x 13
= 1630.72 cm3
So, the volume of the box is 1630.72 cm3.
Problem 6 :
A terrarium is shaped like a rectangular prism. The prism is 25 1/2 inches long, 13 1 / 2 inches wide, and 16 inches deep. What is the volume of the terrarium?
Solution :
Length = 25 1/2 inches ==> 51/2
width = 13 1/2 inches ==> 27/2
height = 16 inches
Volume of terrarium = length x width x height
= (51/2) ⋅ (27/2) ⋅ 16
= 51 ⋅ 27 ⋅ 4
= 5508 cubic inches
Problem 7 :
A block of wood measures 4.5 inches by 3.5 inches by 7 inches. What is the volume of the block of wood?
Solution :
Length = 4.5 inches
width = 3.5 inches
height = 7 inches
Volume of black wood = length x width x height
= 4.5 x 3.5 x 7
= 110.25 cubic inches
Problem 8 :
A restaurant buys a freezer in the shape of a rectangular prism. The dimensions of the freezer are shown. What is the volume of the freezer?
Solution :
Length = 72 1/2 inches ==> 145/2
width = 24 1/2 inches ==> 49/2
height = 36 inches
Volume of black wood = length x width x height
= (145/2) (49/2) 36
= 145 x 49 x 9
= 63945 cubic inches
Problem 9 :
Rectangular prism A measures 6 inches by 4 inches by 5 inches. Rectangular prism B’s dimensions are twice those of prism A. Find the volume of each prism. How many times as great is prism B’s volume as prism A’s volume?
Solution :
Dimension of prism A : Length = 6 inches width = 4 inches height = 5 inches |
Dimension of prism B : Length = 12 inches width = 8 inches height = 10 inches |
Volume of prism A = length x width x height
= 6 x 4 x 5
= 120 cubic inches
Volume of prism B = 12 x 8 x 10
= 960 cubic inches
Volume of prism B / volume of prism A
= 960/120
= 8
So, volume of prism B is 8 times of prism A.
Problem 10 :
Leticia has a small paper weight in the shape of a rectangular prism. The dimensions of the paper weight are shown. What is the volume of the paper weight?
Solution :
Length = 4 1/4 cm ==> 17/4
width = 2 3/4 cm ==> 11/4
height = 5 cm
Volume of paper weight = (17/4) (11/4) 5
= (187 x 5)/16
= 935/16
= 58.43 cubic cm
Problem 11 :
The dimensions of a rectangular prism are 3 1/4 feet by 2 1/2 feet by 5 feet.
Who is correct? Explain.
Solution :
Length = 3 1/4 ==> 13/4
width = 2 1/2 ==> 5/2
height = 5 feet
volume of rectangular prism = (13/4)(5/2) 5
= 325/8
= 40.625 cubic feet
Volume of prims found by Lee :
= 12 1/2 x 3 1/4
= 25/2 x 13/4
= 325/8
= 40.625 cubic feet
Volume of prims found by Lola :
= 16 1/4 x 2 1/2
= 65/4 x 5/2
= 325/8
= 40.625 cubic feet
So, both are correct.
May 21, 24 08:51 PM
May 21, 24 08:51 AM
May 20, 24 10:45 PM