This video explains how to write a given geometric series using sigma notation. The sum is then found.
This video explains how to determine the missing perimeter of two similar rectangles given the ratio of the area.
This video explains how to determine the missing area of two similar rectangles given the ratio of the perimeters.
This video uses two similar triangles to discover the ratio of corresponding sides, perimeter, and area.
This video explains how to perform a conversion using unit fractions and proportions.
This video explains how to use a proportion and a given scale factor to determine the height of a building and the height of 1 floor of the building.
This video uses a tape or bar diagram to explain the meaning of a ratio. The tape diagram is used to determine a number of nuts in a mix.