Math tricks
MULTIPLICATION OF 11 WITH ANY NUMBER OF 3 DIGITS. Let me explain this rule by taking examples 1. 352*11 = 3---(3+5)---(5+2)---2 = 3872 Means insert the sum of first and second digits, then sum of second and third digits between the two terminal digits of the number 2. 213*11 = 2---(2+1)---(1+3)---3 = 2343 EXAMPLE. Here an extra case arises Consider the following examples for that 1) 329*11 = 3--- (3+2) +1--- (2+9-10) ---9 = 3619 Means, if sum of two digits of the number is greater than 10, then add 1 to previous digit and subtract 10 to the associated digit. 2) 758*11 = 7+1---(7+5-10)+1---(5+8-10)---8 = 8338 TO CALCULATE REMINDER ON DIVIDING THE NUMBER BY 27 AND 37 Let me explain this rule by taking examples consider number 34568276, we have to calculate the reminder on diving this number by 27 and 37 respectively. make triplets as written below starting from units place 34.........568..........276 now sum of all triplets = 34+568+276 = 878 divide it by 2