Speed Mathematics - Multiplication
sourabh garg
2015-10-09 19:12:25
if there is alternate number and we want to multiply them so for this we take the mid value and square it(mid value) then subtract 1 from it so we easily get the output of that two alternate number.
for example : 24*26
so middle value is 25
square of 25=625
subtract-1 then
625-1=624
for example : 24*26
so middle value is 25
square of 25=625
subtract-1 then
625-1=624
rajesh
2015-07-28 18:22:10
now i am going to describe the multiplication of two numbers
this method is applied for few numbers like 24*26, 33*37, 42*48
if you observe , sum of unit place digits of two numbers is 10 & tens place digit are same.
so this method is applicable to these numbers only.
24*26
=
6*4=24
2(2+1)=6
so answer is 624
try remaining numbers also..................
this method is applied for few numbers like 24*26, 33*37, 42*48
if you observe , sum of unit place digits of two numbers is 10 & tens place digit are same.
so this method is applicable to these numbers only.
24*26
=
6*4=24
2(2+1)=6
so answer is 624
try remaining numbers also..................
pradeesh
2015-10-11 17:39:38
its not working if above 40
ie 42 * 47
ur ans must be
2014
but ans is 1974
pls say some logic to find this too
ie 42 * 47
ur ans must be
2014
but ans is 1974
pls say some logic to find this too
sam
2015-10-14 04:43:57
Pradeep, read rajesh's post carefully. Sum of unit place digits should be 10
so you cannot apply this to 42*47
42*48 = 2016 which can be done using his method
so you cannot apply this to 42*47
42*48 = 2016 which can be done using his method
chand
2015-07-31 08:58:07
3digit multiplication will be done as follows. multiply 325*432
step-1: u*u= 2*5 = 10, write 0 at unit place. carry=1
step-2: u*t+t*u+1(ie.carry )=20, write 0 at ten place, carry=2
step-3: u*h+h*u+t*t+2(carry) =34, write 4 at hundred place, carry=3
step-4: t*h+h*t+3(carry) = 20 write, 0 at thousand place, carry=2
step-5: h*h+2(Carry ) =14 write 14 at ten thousand place.
ans= 140400
step-1: u*u= 2*5 = 10, write 0 at unit place. carry=1
step-2: u*t+t*u+1(ie.carry )=20, write 0 at ten place, carry=2
step-3: u*h+h*u+t*t+2(carry) =34, write 4 at hundred place, carry=3
step-4: t*h+h*t+3(carry) = 20 write, 0 at thousand place, carry=2
step-5: h*h+2(Carry ) =14 write 14 at ten thousand place.
ans= 140400
manpreet kaur
2013-12-17 11:16:39
Lets multiply two numbers:
56
24
6*4= 24...2 carry-----------4
(4*5)+(6*2)+2(carry above)=34----------4
5*2=1-----------10
so, its 1044
Abhishek
2015-06-17 17:00:57
56
24
BY APPLING CRISS CROSS
6*4=24
5*4+6*2=32+2=34
5*2=10
10+3=13
FINALLY =1344(by taking carry 2,3)
24
BY APPLING CRISS CROSS
6*4=24
5*4+6*2=32+2=34
5*2=10
10+3=13
FINALLY =1344(by taking carry 2,3)
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