how to multiply value from first table with second table

Question

Hi

 TABLE A

ID	Name	Rate	Reference Id
1	a	5	1
2	b	4	1
3	c	2	2
4	d	3	2

 

 TABLE B

tID	Rate	Reference Id	date
1	2	1	01/01/2010
2	3	2	02/02/2014

 

 Now

from the TABLE B get Value of Rate and multiply it with Rate of TABLE A which having TABLE BA.Reference Id  = TABLE B .Reference Id.

 

The Result Should  be like this,

 

ID	Name	Rate	Reference Id
1	a	(5*2) = 7	1
2	b	(4*2) = 8	1
3	c	(2*3) = 6	2
4	d	(3*3) = 9	2

 

Thanks,