Write a direct variation equation that relates x inches to y centimeters. 1 inch = 2.54 centimeters

Answer 1

This problem illustrates the use of The Multiplicative Identity (that is, 1). Any value multiplied by 1 remains the same (although the units may change).

In this problem,

1 = (1 inch) / (2.54 centimeters) = (2.54 centimeters) / (1 inch)

So, to start with x inches and get y centimeters,

y centimeters = (x inches) * ( (2.54 centimeters) / (1 inch) )

Choose the expression that allows units to cancel.

y = 2.54x