Answer:
x = 5 cm
Step-by-step explanation:
Big rectangle
Length = 30 cm
Width = 12.5 cm
Length : width = 30 cm : 12.5 cm
Small rectangle
Length = 12 cm
Width = x cm
Length : width = 12 cm : x cm
Equate the ratios
30 cm : 12.5 cm = 12 cm : x cm
30/12.5 = 12/x
Cross product
30 * x = 12.5 * 12
30x = 150
x = 150/30
x = 5 cm
