Question #bacd4

1 Answer
Jan 12, 2018

#color(blue)(7:20)#

Explanation:

Imagine that they are rectangular posters and the first one has is 7in by 14 in.

Since they similar, use the ratio provided, 7:20, to find the dimensions of the second poster:
#7 * (20/7) = 20#in
#14 * (20/7) = 40#in
The second poster is 20in by 40in.

Now calculate the perimeters of both:
1) #7 + 7 + 14 + 14 = 42#in
2) #20 + 20 + 40 + 40 = 120#in

Finally, write as a ratio and simplify:
#42:120#
#color(blue)(7:20)#

While the ratio of the perimeters remains the same, the area ratio would change.