Unit means one . observation used in unitary method are MULTIPLIACATION and DIVISION
Eg. 3 books cost rs 360. Find the cost of 5 books
Step 1~ ( divide ) cost of i book = 360 divided by 3 = 120
Step 2 ~ ( Multiply ) So cost of 5 books is = Rs 120 multiplied by 5 = 600 ans
So, It's nothing first you have to divide the digits and find the cost of 1 book and then multiply it to the other number in which you have to find the answer thatt was 5 so The cost of 5 books would be 600. So, first divide the find the 1 thing and then multiply to find the real answer with the quotient which came while dividing. And here you have the answer!