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)

Add a new comment... (Use Discussion Board for posting new aptitude questions.)

Name:

Email: (optional)

10 + 10 =
(please answer the simple math question)

Post Your Comment