Counting the number of days in a Quarter from a date range

I'm having a bit of a mind bank with this one...

There are two columns

Start Date | End Date
03/05/2015 28/09/2015
09/09/2015 15/10/2015
...

I'm looking for a formula that would output the number of days from the start to the end date (inclusive) that fall within a certain quarter (pre-selected through a drop down). I have a helper table built in the following format that can be used as a lookup:

Quarter Name | First date in quarter | Last date in quarter
Q3 2015 01/06/2015 30/09/2015
...


So if 'Q3 2015' is selected from the dropdown, in C2 the formula would output 90 (days)

Any suggestions gladly received...

You can take the End Date minus the Start Date + 1.

Example, Start date is in B1, End date is in C1, the number of days between the start and end dates are =C1 - B1 + 1

To get the relevant dates from a dropdown selection, you can use a combination of INDEX / MATCH functions.

E.g. =INDEX(LastDateinQtr, MATCH(DropDown, QuarterNames,0)) - INDEX(FirstDateinQtr, MATCH(DropDown, QuarterNames,0)) + 1

kvsrinivasamurthy - thank you! Worked perfectly