Explanation
Unitary Method comprises of following two steps :
Step 1 = Find the value of one unit.
Step 2 = Then find the value of required units.
Following are some examples explaining Unitary Method.
Example 1 = 5 buses carry 200 passengers. How many passengers can 20 buses carry ?
Answer = The process is as :
Step 1 = Find how many passengers 1 bus carry :
To find this, we have to divide the given number of passengers(200) by given number of buses(5) because one bus will carry less passengers as compared to 5 buses
5 buses carry passengers = 200
1 bus carry passengers = 200 ÷ 5 = 40
Step 2 = Find how many passengers 20 bus carry :
To find this, we have to multiply the required number of buses(20) with number of passengers one bus can carry(40) because more buses will carry more passengers.
1 bus carry passengers = 40
5 buses carry passengers = 40 x 20 = 800.
Alternative Method
Above mentioned method is long. Once you understand the concept of Unitary Method, you can directly apply this method in following ways :
5 buses carry passengers = 200
1 bus carry passengers = (200 ÷ 5)
20 bus carry passengers = (200 ÷ 5) x 20 = 40 x 20 = 800.
Example 2 = 5 worker can complete a work in 20 days. In how many days same work will be completed if 10 workers are employed.
Answer = The process is as :
Step 1 = Find in how many days 1 worker will do the given work.
To find this, we have to multiply the given worker(5) with given number of days(20) because one worker will take more days to complete the given work as compared to 5 workers.
5 workers complete the given works in days = 20
1 worker complete the given works in days = (20 x 5) = 100
Step 2 = Find in how many days 10 worker will do the given work.
To find this, we have to divide numbers of days in which 1 worker will complete(100days) by the required number of workers(10) because more men complete given work in lesser days.
1 worker complete the given works in days = 100
10 workers complete the given works in days = (100 ÷ 10) = 10
Alternative Method
Above mentioned method is long. Once you understand the concept of Unitary Method, you can directly apply this method in following ways :
5 workers complete the given works in days = 20
1 worker complete the given works in days = (20 x 5)
10 workers complete the given works in days = (20 x 5) ÷ 10 = 100 ÷ 10 = 10

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