Yes, price of an item can go up by 90%. In fact, it can go up even by 100% or 150% too.

If the price was rs. 100 and it becomes rs 220
then increase = 220-100 = 120
% increase = 120/100 * 100 = 120%

So it can go up by anything.
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i hope the price of items do not go up by 90%... i hope they remain at the same rates..
in real life.. i hope not they go up so much
They do go up! When the rate of onion went up for the first time, it became around Rs. 100 per kg from around Rs. 20 per kg.