English

The Internal Dimensions of a Rectangular Box Are 12 Cm Xx Cm X9 Cm. If the Length of the Longest Rod that Can Be Placed in this Box is 17 Cm; Find X - Mathematics

Advertisements
Advertisements

Question

The internal dimensions of a rectangular box are 12 cm x  `x` cm x 9 cm. If the length of the longest rod that can be placed in this box is 17 cm; find `x`.   

Sum

Solution

Length of longest rod = Length of the diagonal of the box

17 = `sqrt(12^2 + x^2 + 9^2)`
172 = 122 + x2 + 92
x2 = 172 - 122 -9
x2 = 289 - 144 - 81
x2 = 64
x = 8 cm  

shaalaa.com
Cross Section of Solid Shapes
  Is there an error in this question or solution?
Chapter 21: Solids [Surface Area and Volume of 3-D Solids] - Exercise 21 (C) [Page 274]

APPEARS IN

Selina Concise Mathematics [English] Class 9 ICSE
Chapter 21 Solids [Surface Area and Volume of 3-D Solids]
Exercise 21 (C) | Q 3 | Page 274

RELATED QUESTIONS

The following figure shows a solid of uniform cross-section. Find the volume of the solid. All measurements are in centimeters.
Assume that all angles in the figures are right angles.


The following figure shows a closed victory-stand whose dimensions are given in cm.

Find the volume and the surface area of the victory stand. 


A rectangular water-tank measuring 80 cm x 60 cm is filled form a pipe of cross-sectional area 1.5 cm2, the water emerging at 3.2 m/s. How long does it take to fill the tank?


A school auditorium is 40 m long, 30 m broad and 12 m high. If each student requires 1.2 m2 of the floor area; find the maximum number of students that can be accommodated in this auditorium. Also, find the volume of air available in the auditorium, for each student. 


Find the length of a solid cylinder of diameter 4 cm when recast into a hollow cylinder of outer diameter 10 cm, thickness 0.25 cm and length 21 cm? Give your answer correct to two decimal places.


The cross section of a piece of metal 2 m in length
is shown. Calculate the volume of the piece of metal.


The figure shows the cross section of 0.2 m a concrete wall to be constructed. It is 0.2 m wide at the top, 2.0 m wide at the bottom and its height is 4.0 m, and its length is 40 m. Calculate the cross sectional area


The cross section of a tunnel perpendicular to its length is a trapezium ABCD as shown in the figure. AM = BN; AB = 4.4 m, CD = 3 m The height of a tunnel is 2.4 m. The tunnel is 5.4 m long. Calculate the cost of flooring at the rate of Rs.2. 5 per m2.


ABCDE is the end view of a factory shed which is 50 m long. The roofing of the shed consists of asbestos sheets as shown in the figure. The two ends of the shed are completely closed by brick walls.

Calculate the total volume content of the shed.


ABCDE is the end view of a factory shed which is 50 m long. The roofing of the shed consists of asbestos sheets as shown in the figure. The two ends of the shed are completely closed by brick walls.


If the cost of asbestos sheet roofing is Rs. 20 per m2, find the cost of roofing.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×