Unit Conversion using Algebraic Substitution

It was great that my Chair, Iain McNab, was able to join us for our screencasting day. This is a great example of how different approaches may make more sense to different students, depending on their thinking.

Direct Variation – both methods

Given y is directly proportional to x and y46 when x62, find y when x17.

Proportions – Solving for the variable

Student solution for solving for x in a proportion by cross-multiplication.

Solving for x in a proportion

Solving for x in a proportion

Unit conversion – seconds to days

Student solved problem where seconds are converted to days.

Indirect Variation – both methods

Given y is indirectly proportional to x and y95 when x54, find y when x17.