Free practice · single-choice · medium
Practice
Recognize a broken proportional model
A delivery cost includes USD 4 per box plus one fixed USD 30 dispatch fee. Which statement is correct?
Ratio direction map
Label both quantities before reducing to a per-one rate
- LabelQuantity A compared with B
- DirectChoose the requested per-unit direction
- ReduceDivide both parts consistently
- ScaleApply one factor to both parts
- CheckUnits and cross-products agree
Direction determines meaning. Preserve the numerator and denominator units, scale both parts together, and substitute the result to check the relationship.