Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids (Representing 3-D in 2-D)

Selina Publishers Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids (Representing 3-D in 2-D)

Recognition of solids Exercise 18 – Selina Concise Mathematics Class 7 ICSE Solutions

Question 1.
Identify the nets which can be used to form cubes
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids Q1
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids 1

Question 2.
Draw at least three different nets for making cube.
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids 2

Question 3.
The figure, given below, shows shadows of some 3D objects, when seen under the lamp of an overhead projector :
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids Q3
In each case, name the object.
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids 3

Question 4.
Using Euler’s formula, find the values of a, b, c and d.
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids Q4
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids 4

Question 5.
Dice are cubes with dot or dots on each face. Opposite faces of a die always have a total of seven on them.
Below are given two nets to make dice (cube), the numbers inserted in each square indicate the number of dots in it.
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids Q5
Insert suitable numbers in each blank so that numbers in opposite faces of the die have a total of seven dots.
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids 5

Question 6.
The following figures represent nets of some solids. Name the solids
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids Q6
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids 6

Question 7.
Draw a map of your class room using proper scale and symbols for different objects.
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids 7

Question 8.
Draw a map of your school compound using proper scale and symbols for various features like play ground, main building, garden, etc.
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids 8

Question 9.
In the map of India, the distance between two cities is 13.8 cm.
Taking scale : 1 cm = 12 km, find the actual distance between these two cities.
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 18 Recognition of Solids 9

Selina Concise Mathematics Class 7 ICSE Solutions