0

100 x 20 = (100)·(20) = (100 + 0)·(20 + )
= 20x100 + 0x10 + (   )x10 + 0 =
= 2000 + 0 + (   )x10 + 0 =     2000

1

-9

-8

-7

-6

-5

-4

-3

-2

-1

0

  1 of 12

FirstOuterInnerLast

 

Level

1

2

3

4

How Many

5

10

20

30

50

  

FOIL method @

 

Example >>>

 34 x 52 =  (30 + 4)·(50 + 2)

 

 

 

  

First

(A + B)·(C + D) = AC + AD + BC + BD

= 30 x 50

= 1500

Outer

(A + B)·(C + D) = AC + AD + BC + BD

= 30 x 2

=     60

Inner

(A + B)·(C + D) = AC + AD + BC + BD

= 4 x 50

=   200

Last

(A + B)·(C + D) = AC + AD + BC + BD

= 4 x 2

=       8

 

 

    

 

  

 

= 1768