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Two quantities are in direct proportion when, as one increases:
AThe other decreases in the same ratio
BThe other stays exactly the same
CThe other increases so their ratio stays constant
DThe other increases by the same fixed amount
Answer & Solution
Correct answer: C. The other increases so their ratio stays constant
1. Direct proportion is about the ratio of the two quantities, not their difference.
2. As the weight of sugar increases, its cost also increases in such a manner that their ratio remains constant.
3. So doubling one quantity doubles the other.
4. Option D describes adding a fixed amount, which would change the ratio at every step.
5. Option A describes inverse proportion, the opposite relationship.
_Source: NCERT Class 8 Maths, Ch 11 'Direct and Inverse Proportions', S11.2 Direct Proportion_
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