The scale factor 1 : 3 means:
[tex]\frac{\text{ side length of the original figure}}{side\text{ length of the new figure}}=\frac{1}{3}[/tex]Cross multiplying, we get:
[tex]\text{side length of the original figure}\cdot3=\text{side length of the new figure}[/tex]If the original figure has the measures 5 in and 3.5 in, then new lengths are:
3x5 = 15 in
3x3.5 = 10.5 in
