That doesn't make any sense, tolerance is the tolerated range of values i.e. 240V with a tolerance of 10% is 216V to 254V.
You mean the voltage is 240VAC 50Hz.
I researched it for you.
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If the transformer is 120V, it will require another transformer to convert the 240V to the 120V required for your transformer.
If the transformer is 100V to 240V then it will be fine because it means it can accept any voltage between 100V to 240V.