Practice Problem: Geometry - 1 | Mathematics for Class 4 PDF Download

Q1: Fill in the blanks: 
(a) A portion of a ________ is called a line segment. 

line

(b) A ________ has two end points. 

line segment

(c) A ________ can be extended to any length on both sides. 

line

(d) A line has no fixed ________. 

length

(e) A _________ is that closed curve which does not cross itself. 

simple closed curve

(f) A simple closed curve made of line segments only is called a ______ .

polygon 

(g) A polygon which is made of _______ line segments is called a triangle. 

three

(h)The line segments that form the triangle are called its ________. 

sides

(i) The point where two sides of a triangle meet is called its ______. 

vertex

(j) A simple closed figure bounded by 4 line segments is called a ______. 

quadrilateral

(k) Line segment joining two opposite vertices of a quadrilateral is called_____.

diagonal

(l) Diameter is _____ that of radius. 

twice

(m) A quadrilateral having all sides equal is called a _______. 

rhombus

(n) The sum of length of line segments of a figure is called its _________. 

perimeter

Q2: The radii of the circle are given. Find their diameters: 
I. 9 cm 

Diameter = 2 × 9 = 18cm

II. 12 cm 

Diameter = 2 × 12 = 24cm

III. 4 m 

Diameter = 2 × 4 = 8m

IV. 16 dm 

Diameter = 2 × 16 = 32dm

Q3: Find the radii of the diameter are: 
I. 28 dm 

Radius = 28/2 = 14 dm

II. 44 m 

Radius = 44/2 = 22 m

III. 50 dm 

Radius = 50/2 = 25 dm

IV. 18 cm

Radius = 18/2 = 9 cm

Q4: Sonia wants to put lace along the edges of her table mats 30 cm long and 20 cm wide. Find the length of lace for 6 mats. 
Ans: Step 1: Calculate the perimeter of one mat
The formula for the perimeter P of a rectangle is:
P = 2 × (Length + Width)
For one mat, the length is 30 cm and the width is 20 cm.
So, the perimeter of one mat is:
P = 2 × (30 + 20) = 2 × 50 = 100cm
Step 2: Calculate the total length of lace for 6 mats
Since the perimeter of one mat is 100 cm, for 6 mats, the total length of lace needed will be:
Total length of lace = 100 × 6 = 600cm

Q5: A rectangular garden is 79 metres long and 55 metres wide. Find the length of wire needed to fence it thrice.
Ans: Step 1: Calculate the perimeter of the rectangle
The formula for the perimeter P of a rectangle is:
P = 2 × (Length + Width)
Given:

• Length = 79 meters 
• Width = 55 meters

Substitute the values into the formula:
P = 2 × (79 + 55) = 2 × 134 = 268meters
Step 2: Find the total length of wire for three fences
To fence the garden three times, we multiply the perimeter by 3:
Total length of wire = 268 × 3 = 804meters

Q.6 A boy walks around a triangular garden whose sides are 17m, 23m and 19m. Find the distance he covers if he walks around it 5 times.
Ans: Step 1: Calculate the perimeter of the triangle
The perimeter P of a triangle is the sum of its three sides:
P = Side 1 + Side 2 + Side 3
Given:

• Side 1 = 17 meters
• Side 2 = 23 meters
• Side 3 = 19 meters

Substitute the values: P = 17 + 23 + 19 = 59meters
Step 2: Find the total distance the boy covers
To find the total distance he covers by walking around the garden 5 times, multiply the perimeter by 5:
Total distance = 59 × 5 = 295meters