Question

If the scale factor of figure a to figure b is 7:2 find the perimeter of figure a whenever the perimeter of figure b is 35

Answer 1

Answer:

122.5

Step-by-step explanation:

The scale factor of two figures is the ratio of the corresponding sides or in this case the perimeters. The scale factor of figure a to figure b is 7:2 this means that for 7 units of perimeter on the a figure, there are 2 units of perimeter on the b figure.

To obtain the perimeter of the figure a we arrange the equation (the ratio is maintained so both sides of the equation are equal):

$\frac{7}{2}=\frac{x}{35}$

where x will be the perimeter of figure a. We solve for a like this:

$x=\frac{35*7}{2}=122.5$

a figure perimeter is 122.5

Answer 2

a        7           P

        -------= --------

b        2              35

Using cross products

7*35 = P*2

P = 7*35/2

P = 122.5