How to Convert Comma(,) to Point(.) in numbers data

Hi, I have a problem in data I got which given in comma(,) as separation for decimal places. How can I convert automatically all of those comma sign to point(.) in excel other than change them in traditional way which deleting them one by one?

eg.
294,78 3,29 0,89 27,05
296,49 18,36 5,21 28,38
298,20 20,96 4,94 23,57
299,90 22,21 5,79 26,07
301,61 34,95 10,33 29,56
303,31 51,81 13,48 26,02
305,01 66,89 15,45 23,10
306,71 79,63 23,74 29,81