AMO Grade 4 · 7. Money, rates, motion and work
Find the amount for one unit, suppose all objects are the same kind, count gaps instead of trees, and add speeds or work per hour.
Use a unit rate and change units of time and money correctly.
Solve chickens-and-rabbits problems by supposing all objects are one kind.
Count trees, posts, cuts and floors by counting the gaps.
Use distance = speed × time for meeting and catching-up problems.
Find the time for workers working together or many workers over many days.