Question

Alex made a sketch for a poster contest. The sketch measures 4 in. × 5 in. The scale factor from the sketch to the finished poster was 2 in. to 5 in.

What were the dimensions of the poster?

Answer 1

well interesting, the scale means that when you have 2in on the sketch , the poster should have 5in

Answer 2

well this way:
SKETCH POSTER
2 ---------> 5
4 --------> X

we write an equation 2 x = 4 (5)
x = 20 / 2 x = 10

Answer 3

then do the same for 5in

Answer 4

4 has been converted to 10
now we must convert 5
SKETCH POSTER
2 ---------> 5
5 ---------> x

2 x = 5 (5)
x = 25 / 2 x = 12,5

Finally the dimensions of the poster are 10 in x 12,5 in