Converting fresh fruit to dry fruit by preserving solids: Fresh fruit contains 72% water (28% solids). Dry fruit contains 20% water (80% solids). From 100 kg of fresh fruit, how many kilograms of dry fruit can be obtained (solids conserved)?

Introduction / Context:
Drying removes water but keeps the solids mass unchanged. Therefore, equate the solids in the fresh fruit to the solids in the final dry fruit to compute the final dry mass.

Given Data / Assumptions:

• Fresh fruit = 100 kg with 28% solids ⇒ 28 kg solids.
• Dry fruit has 80% solids (since water = 20%).

Concept / Approach:
Let W be the dry fruit mass. Then solids conservation gives 0.80 * W = 28. Solve for W directly.

Step-by-Step Solution:

Verification / Alternative check:
Water in dry fruit = 20% of 35 = 7 kg; solids 28 kg, equal to fresh solids, consistent.

Why Other Options Are Wrong:
30–33 kg would imply solids below 28 kg at 80% solids content; 32 kg corresponds to only 25.6 kg solids.

Common Pitfalls:
Averaging percentages or changing solids content; the only invariant is solids mass.

Final Answer:
35 kg