Question

Fresh grapes contain $90\%$ water by weight while dried grapes contain $20\%$ water by weight. What is the weight of dry grapes available from $20$kg of fresh grapes?

• A. $2$kg
• B. $2.4$kg
• C. $2.5$kg
• D. $3$kg

Answer 1

Answer: (C)

$2.5$kg

90% of the weight of the fresh grapes is water, so 10% is not water.

$10\%\ast 20kg=2kg$ of totally waterless grapes.

Dried grapes contain 20% water. So 80% of the weight of dried grapes is not water.

$80\%\ast DriedGrapeWeight=2kg$

So Dried Grape Weight $=\frac{2Kg}{80\%}=2.5kg$.