From least to greatest 2.62, 2 2/5, 26.8 %, 2.26 and 271 %

Now before we put them in the order of least to greatest, we have to make sure that all items are the same format. So first, let's convert them to decimal. The ones that are of different format are 2 2/5, 26.8% and 271%. So 2 2/5 can be presented a 2.4, 26.8 is 0.268 and 2.71% is 2.71. Now with this, we can arrange the items from least to greatest. The order of this will be as follows:

0.268 as the smallest number of the five then followed by, 2.26, 2.4, 2.62, and 2.71 as the greatest.