Multiplying any Number with 111, 1111, etc using Speed Mathematics

If you have not gone through to the topic Multiplication by 11 , please read it before proceeding further.

Example 1

Calculate 752 * 111

Solution

Step 1: Three ones are there in 111. So we have to keep adding maximum to the depth of three. So the digits in the answer will be 7 , 7+5 , 7+5+2, 5+2, 2

=> 7, 12, 14, 7, 2

Step 2: If the sum of digits is a two digit number, the left digit is considered as a carry digit, In this case, 1 is carry digit for 12 and 2 is written. 1 is carry digit for 14 and 4 is written. So this can be written as

7, 2(carry=1), 4(carry=1), 7, 2

Step 3: Carry digits will be added to its left digit.

=> 7+1, 2+1, 4, 7, 2

=> 8, 3, 4, 7, 2

Step 4: Yes, you have got the answer now . Just put these digits together.

i.e., the answer is 83472

Example 2

Calculate 57 * 111

Solution

Step 1: Three ones are there in 111. So we have to keep adding maximum to the depth of three. Also to make 57 compatible with 3 digits, it is written as 057. So the digits in the answer will be 0 , 0+5 , 0+5+7, 5+7, 7

=> 0, 5, 12, 12, 7

Step 2: If the sum of digits is a two digit number, the left digit is considered as a carry digit, In this case, 1 is carry digit for 12 and 2 is written. So this can be written as

0, 5, 2(carry=1), 2(carry=1), 7

Step 3: Carry digits will be added to its left digit.

=> 0, 5+1, 2+1, 2, 7

=> 0, 6, 3, 2, 7

Step 4: Yes, you have got the answer now . Just put these digits together.

i.e., the answer is 06327 or 6327

Example 3

Calculate 1257 * 1111

Solution

Step 1: Four ones are there in 1111. So we have to keep adding maximum to the depth of four. So the digits in the answer will be 1, 1+2 , 1+2+5, 1+2+5+7, 2+5+7, 5+7, 7

=> 1, 3, 8, 15, 14, 12, 7

Step 2: If the sum of digits is a two digit number, the left digit is considered as a carry digit, In this case, 1 is carry digit for 15 and 5 is written. 1 is carry digit for 14 and 4 is written. 1 is carry digit for 12 and 2 is written. So this can be written as

1, 3, 8, 5(carry=1), 4(carry=1), 2(carry=1), 7

Step 3: Carry digits will be added to its left digit.

=> 1, 3, 8+1, 5+1, 4+1, 2, 7

=> 1, 3, 9, 6, 5, 2, 7

Step 4: Yes, this is the answer . Just put these digits together.

i.e., the answer is 1396527.

 
 
 
Comments(19) Sign in (optional)
showing 1-10 of 19 comments,   sorted newest to the oldest
Himanshu
2015-09-11 03:09:34 
i didn't get ans. of this
938*111 pls solve
(0) (0) Reply
Raj (Senior Maths Expert, careerbless.com)
2015-09-11 11:32:38 
938*111

9  (9+3)  (9+3+8)  (3+8)  8

9  (2, c=1)  (0, c=2)  (1, c=1)  8

10  4  1  1  8

i.e., 104118
(0) (0) Reply
tejaswini
2015-08-22 08:31:27 
by using the above method i need the answer for
6752×111
(0) (0) Reply
jay
2015-08-25 21:43:11 
6752×111

6 (6+7) (6+7+5) (7+5+2) (5+2) 2
6 3(c=1) 8(c=1) 4(c=1) 7 2
7 4 9 4 7 2

Ans is 749472
(0) (0) Reply
Jay
2014-06-08 10:50:51 
3rd examples answer is wrong as 1257*111=139527....so is der any fault in d method with 4 digit no or der is any other method 2 solve it
(0) (0) Reply
s
2014-09-02 05:02:54 

Calculate is for  1257 * 1111 not  1257 * 111

(0) (0) Reply
hemant
2014-06-11 16:38:03 
see here is another method

111*1257 --- add those numbers

1257+12570+125700 ---- add one zero from the second digit of 111

suppose 11111*1257 ---- add those numbers

1257+12570+125700+1257000+12570000 ---- add one zero from the second digit of 11111
(0) (0) Reply
Jay
2014-06-10 10:22:49 
3rd example is 1257 * 1111 = 1396527 which is correct
(0) (0) Reply
san
2014-03-07 03:47:31 
  1. 19385679*1111=?(how to solve
(0) (0) Reply
Jay
2014-03-07 20:24:28 
19385679*1111

1    1+9         1+9+3     1+9+3+8   9+3+8+5   3+8+5+6  8+5+6+7  5+6+7+9  6+7+9    7+9         9
1     10             13           21           25              22           26               27         22           16           9
1     (c=1) 0    (c=1) 3    (c=2)1    (c=2) 5       (c=2) 2     (c=2) 6       (c=2) 7  (c=2)2     (c=1) 6    9
1+1   0+1        3+2          1+2        5+2          2+2            6+2            7+2        2+1          6         9
2       1             5              3             7               4                8                9            3            6        9

ie 21537489369 is the answer
(0) (0) Reply
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