Answer:
21 feet
Explanation:
The problem bothers on the dimension of a scaled drawing/prototype
The indications on the blueprint actually represent the scale
that is 1 inch: 3.5 feet
Given that a wall is 6 inches on the blueprint, now, in reality, the actual
length will be 3.5*6= 21 feet
what is a scaled drawing?
Usually, the scale is given as a ratio. A drawing, which has been reduced or enlarged or a drawing whose dimensions have been changed to a particular size other than its previous or initial size is a scaled drawing.