Answer: 4 in × 6 in will form a similar rectangle with the sign.
Step-by-step explanation:
The sign and the postcard are rectangles. If we reduce the size of the sign to postcard, the most suitable postcard size would be the size the one that would be similar in size to the sign. This means that the dimensions of the sign would be reduced by a common factor.
Therefore, the common factor is
Length of sign/ length of postcard = width of sign/width of postcard
Therefore, the most suitable post card size is 4 in × 6 in.
Common factor = 5/4 = 7.5/6 = 1.25
