Problems in Arithmetic

Introduction to problems in arithmetic:

Directly or indirectly we use arithmetic's in our day-to-day life. The literacy rate is calculated by 3 steps namely ‘Read’, ‘write’ and ‘arithmetic’. From this we can conclude that arithmetic takes an important role in our daily life. For successful life one must know the values of arithmetic. Some arithmetic topics are given below.

1. Ratio

2. Proportion

2. Percentage.

Example Problems on Arithmetic

Ex:1 In a classroom there are 25 boys and 15 girls. What is the ratio between number of boys and number of girls?

Sol:

The ratio between the number of boys and number of girls =25/15
When reduced to lowest form =5/3
It is customary to write this ratio as 5 : 3
Ratio between the number of boys and girls = 5 : 3

Ex:2 The age of Ramu’s father is 40 years and that of Ramu is 10 years. What is the ratio between the father’s age and Ramu's age?

Sol:

Ratio between the father's age and Ramu's age  = 40 : 10
=  4 : 1

Ex:3 The cost of a notebook is Rs. 20 and the cost of a pen is Rs. 15. What is the ratio between the cost of a notebook and the cost of a pen?

Sol:

Ratio between the cost of a note book and the cost of a pen = 20 : 15
=  4 : 3

More Problems on Arithmetic

Ex:1 The ratio of rectangle is 4 : 3. If the breadth is 21 cm, find the length?

Sol:
Breadth = 21 cm
The ratio of length to breadth is 4 : 3
Breadth = 3 parts
3 parts = 21 cm
1 part =21
3 cm = 7 cm
Length = 4 parts
4 parts = 4 × 7 cm = 28 cm
Length of the rectangle = 28 cm

Ex:2 The monthly salary of Meena is Rs. 4000. She spends 80% of her salary every month. How much does she save every month?

Sol:
Meena's monthly salary = Rs. 4000
Expenditure = 80% of 4000
= (80/ 100) × 4000

= Rs. 3200
Savings = 4000 – 3200 = Rs. 800.