19. if the scale is 1: 100 on a plan, and a fence is 7,500 mm,
how many millimetres will it measure on the plan?
mm

It will measure 75 millimetres on the plan.

Step-by-step explanation:

Given:

Scale on the plan = 1:100

Length of the fence =  7,500 mm

To find:

how many millimetres will it measure on the plan

Solution:

As the ratio on the plan is 1: 100, the for 7500 the ratio will

x : 7500

Now by cross multiplication we get

x = 75

the answer is 15% decrease