a Write the ratio of a model length to an actual length.
B
b Multiply the scale by a conversion factor to get a unitless ratio.
A
a 6in.:50ft
B
b 1/100
Practice makes perfect
a We are given that Carlos made a scale model of a local bridge, and we are asked to evaluate the scale of the model. To do this, we will write the ratio of model length to actual length.
model length/actual length=6in./50ft
The scale of the model is 6in.:50ft.
b In this part, we are asked to find the scale factor Carlos used to build his model. We will multiply the scale we found in the previous part, 6in.50ft, by a conversion factor that relates inches to feet, which is 1ft12in..
