Calculations Made Easy.....

This is a shortcut for doing mathematical calculations easily।These are in use for a long time.I am just trying to gather them here. For this particular piece thanks to my friends Gulu and Tanuja,who helped me to understand this.So,lets start.

1>To multiply any number with a number having all 1's(e.g. 11,111,1111 etc.)

i>Count the number of 1's
ii>Start from right.
Put the right-most digit(RMD) in the right-most place of the answer
iii>Add the two RMDs and put the sum in the left of the already present digit in the answer.
iv>Keep on doing this until you add the same number of RMDs present in the multiplier
v>When this has been achieved, start to lessen the digits to add one by one.
vi>Always add the carry to the next addition.

Perhaps you did understand.So, here is an example.

4 3 5 2
* 1 1 1
------------------
2 [RMD,so placing it without change]
7 [The two RMDs,5+2=7]
0 [The three RMDs,2+5+3=10,placing 0 and carrying 1]
3 [As the multiplier has three 1s,so we are adding only three digits at most,
5+3+4=12+1=13,1 was carried over,so 3 is placed and 1 is carried]
8 [Adding the two Left-most digits,4+3=7+1=8]
4 [The LMD is placed as it is]
---------------------
483072 [This is the answer]

Is it clear enough.I would give some more examples on comming days...till then practice hard.Bye and take care