Extract data from One dataGrid into another DataGrid.

I have two data gridveiw in my form, in one data grid I am importing excel file to display all the data which is working fine, now I need to extract some columns data from main gird which is holding all the data and display in to another DataGrid which is Datagrid2 when a click event is executed. However there is one catch, main data gridveiw1 got the following data

Code	Q2	Q3	Q4
1001	Some data	No	Very Easy
1001	Some data	No	Very Easy
1001	Some data	No	Very Easy
1001	Some data	No	Quite Easy
1001	Some data	No	Quite Easy
1001	Some data	No	OK
1001	Some data	Yes	A bit difficult
1002	Some data	No	Very Easy
1002	Some data	No	Very Easy
1002	Some data	No	OK
1002	Some data	No	Quite Easy
1002	Some data	No	Quite Easy
.	.	.	.
.	.	.	.
.	.	.	.
.	.		.

Desired Output

Code	Questions	Percentage
1001	Q3	85%
1001	Q4	71%
1002	Q3
1002	Q4
1003	Q3
1004	Q4

Know what I need is to merge the data e.g. first count how many time 1001 in the column Code and then count how many times "No" is in the column Q3 than its just 6 / by total number of 1001 which is 85%, but some time the total number of responses exceeds 7.
I will figure out Q4, its same as Q3 but Very Easy and Quite Easy = 1 and rest is 0 and other calculation is same.
So, can someone please help me with this one please......
Thanks..