We always used the normal way of multiplication while multiplying any number with 11. The former method is like
2678
x11
2678
2678x
29458
Now with trick
write a 0 on both the sides of the number
026780
(abcdef)
Now starting from the end start adding the two number in the format
(a+b)(b+c)(c+d)(d+e)(e+f)
If the any added number generates a number greater than 9 like 10, 12, 15 carry the number and add it to the to the left. So the answer for 2678*11 with trick format is
026780
(abcdef)
(a+b)(b+c)(c+d)(d+e)(e+f)
(0+2)(2+6)(6+7)(7+8)(8+0)
(2)(8)(13)(15)(8)
Now this would be
carrying 1 from 15 and adding to 13 makes it 14
(2)(8)(14)58
carrying 1 from 14 and adding to 8 makes it 9
(2)(9)458
29485
So this is a trick to multiply any number with 11
Try it yourself
Teach your kids the trick to make Maths intersting and easy for them.
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