Two small javascript tasks

I need two small html/javascript jobs for a free blog I run: one is a daily total in a small panel that says: Follow Dining in For £ess and you will have saved: £[login to view URL] - this sum in British pounds to increment daily by 7.85714285714286 but to show two characters after the decimal point. I should be able to stipulate the starting date - so after seven days the total should read £55.00 and after 14 days it should read £110.00 the second is a simple calculator that should read: [1] How many in your family? [user input] ## [2 ] How much is your current weekly spend on meals? [user input] £###.## (British pound sign) [3] Your dininginforless weekly budget should be: £##.## [calculation that divides [2] by [1] and multiplies by 1.40625 [4] Making a weekly saving of £###.## [calculation of [2] minus [3] That is, per year: £###.## [calculation of [4] divided by 7 and multiplied by 365 Thanks