work problem with fractions

[Jules]

If 1/4 inch represents 1 foot on a blueprint, how many inches on the drawing will be required to represent 18 feet?

 

[Goistein]

Use proportions: (1/4)/1=x/18. Cross-multiplyto get x=(1/4)*18=9/2. Or just multiply 18*1/4=18/4=9/2.