@Njung'e:
not quite that easy. The calculators don't have memory. Thus if you buy 7 packets of milk @ 26 bob and two loaves of bread @ 33 bob you have to do the following:
punch in 26 x 7 and get the answer (182)
write answer 1 on a piece of paper
punch 33 x 2 and get 66
now add the answer for the milk (182) to this figure to get final result...248
Now that sound easy since there only two products.....but if you doing your end-of-month shopping,the calculator will be of little use.
I don't think Uchumi is doing it themselves,they must have been approached by some enterprising fellow..who will charge companies for placing ads and pay Uchumi for putting the calculators on the trolleys.
Nothing is real unless it can be named; nothing has value unless it can be sold; money is worthless unless you spend it.