Subtraction Shortcuts

Recommended -Calculate Mentally (Don't use pen, paper and pencil)

It is very useful tip.Just take it in your habit.

Example-1	Example-2
216 - 87  (Take last 2 digits at a time from both numbers .If left 2 digit is less then 2 digit of right side than borrow 1 from neighbor.Here 16<87 so 16 can borrow 1 from his neighbor i.e from 2.Now we can write 16 as 116 ) = 100 +116-87 (neighbor is now 2-1=1) =  100+29 = 129	510 - 296  Take last 2 digits at a time from both numbers .If left 2 digit is less then 2 digit of right side than borrow 1 from neighbor.Here 10<96 so 10 can borrow 1 from his neighbor i.e from 5.Now we can write 10 as 110 ) =400+(110-96)-200 =200+14 =+214
Example-3	Example-4
250 - 97 = 250 - (100 - 3) = 250 - 100 + 3   // subtract 100 then add 3 = 150 + 3 = 153	250 - 197 = 250 - (200 - 3) = 250 - 200 + 3      // subtract 200 then add 3 = 50 + 3 = 53

Example-5
216 - 61 = 216 - (100 - 39)                                                                                                                                     = 216 - 100 + 39 = 116 + (40 - 1) = 156 - 1 = 155

 Practice Time:

Recommended-Do it in 3 min

1-     215  -  28
2-    197   -  88
3-    587   -  91
4-    856   -  87
5-    566   -  76
6-    456   -  156
7-    9956  -  786
9-    4444  -  555
10-  234    -   67