Question

A wet food product contains 70% water. After drying, it is found that 70% of original water has been removed. The mass of water removed per kilogram of wet food is:

• A. 4.9 kg
• B. 49 kg
• C. 0.49 kg
• D. 0.049 kg

Hint:

To calculate the mass of water removed, multiply the percentage of original water removed by the initial amount of water in the food.

Answer 1

The Correct Option is C

Given that the wet food contains 70% water, we can express the amount of water in 1 kg of the wet food as: \[ {Initial water} = 70% { of 1 kg} = 0.70 \, {kg} \] After drying, 70% of the original water has been removed. The mass of water removed is therefore: \[ {Water removed} = 70% \times 0.70 \, {kg} = 0.49 \, {kg} \] Thus, the mass of water removed per kilogram of wet food is 0.49 kg.
Now, let's examine the options:
- Option (1) 4.9 kg is incorrect. This value would be relevant if the food contained 100% water.
- Option (2) 49 kg is incorrect. This is far too large for 1 kg of wet food.
- Option (4) 0.049 kg is also incorrect. This is too small when considering the mass of water in 1 kg of food.
Thus, the correct answer is 0.49 kg.