- Data Structure
- Networking
- RDBMS
- Operating System
- Java
- MS Excel
- iOS
- HTML
- CSS
- Android
- Python
- C Programming
- C++
- C#
- MongoDB
- MySQL
- Javascript
- PHP
- Physics
- Chemistry
- Biology
- Mathematics
- English
- Economics
- Psychology
- Social Studies
- Fashion Studies
- Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Find the common factors of:
(a) 20 and 28
(b) 15 and 25
(c) 35 and 50
(d) 56 and 120
To do :
We have to find the common factors of the given pairs of numbers.
Solution :
(a) Factors of 20 are
$20 = 1\times 20$
$= 2\times 10$
$= 4\times 5$
Therefore, factors of 20 are 1,2,4,5,10 and 20.
Factors of 28 are
$28 = 1\times 28$
$= 2\times 14$
$= 4\times 7$
Therefore, factors of 28 are 1,2,4,7,14 and 28.
The common factors of 20 and 28 are 1,2 and 4.
(b) Factors of 15 are
$15 = 1\times 15$
$= 3\times 5$
$= 15\times 1$
Therefore, factors of 15 are 1,3,5 and 15.
Factors of 25 are
$25 = 1\times 25$
$= 5\times 5$
$= 25\times 1$
Therefore, factors of 25 are 1,5 and 25.
The common factors of 15 and 25 are 1 and 5.
(c) Factors of 35 are
$35 = 1\times 35$
$= 5\times 7$
$= 35\times 1$
Therefore, factors of 35 are 1,5,7 and 35.
Factors of 50 are
$50 = 1\times 50$
$= 2\times 25$
$= 5\times 10$
$= 10\times 5$
$= 50\times 1$
Therefore, factors of 50 are 1,2,5,10,25 and 50.
The common factors of 35 and 50 are 1 and 5.
(d) Factors of 56 are
$56 = 1\times 56$
$= 2\times 28$
$= 4\times 14$
$=7\times8$
$=56\times1$
Therefore, factors of 56 are 1,2,4,7,8,14,28 and 56.
Factors of 120 are
$120 = 1\times 120$
$= 2\times 60$
$= 3\times 40$
$= 4\times 30$
$= 5\times 24$
$= 6\times 20$
$= 8\times 15$
$= 10\times 12$
$= 120\times 1$
Therefore, factors of 120 are 1,2,3,4,5,6,8,10,12,15,20,24,30,40,60 and 120.
The common factors of 56 and 120 are 1,2,4 and 8.