Ratios & Proportions
Reduce the ratio to one part first. If trucks to vans is 3 to 2 and there are 18 trucks, one part is 6, so the 2 parts of vans are 12. Most wrong answers on these items come from multiplying by the ratio upside down, so before you commit, ask yourself which quantity is supposed to be bigger.
15 original questions in this topic set.