To solve this you must set up what is called a proportion. A proportion is a way of comparing two comparing values where one of the four values is missing. In your problem the missing value is the height of the smallest tree in the model.
To set up a proportion, you need all of your values. The easiest way to do this is to list them:
Highest tree in real life: 40ft
Highest tree in model: 10ft
Smallest tree in real life: 4ft
Smallest tree in model: x
So know you can set your proportion like this:
40/4 = 4/x
(When setting up a proportion, you always want to have the values belong to each other. For example don't put the height of the small tree in the model underneath the value of the highest tree in real life.)
So know to find what the x values equals, we need to cross multiply. And then all that's left after that is to solve for x.
40 times x = 4 times 4
40x = 16
x = 2.5
The smallest tree in the model should equal 2.5 feet.
Hope this helps! :)
The answer to the question is sound
Get your numbers gathered up and solve the problem in the ordered step
Personally, I know that I don't however it all depends on the person's lifestyle, health, and resoucres, such as if they are able to complete the excersise or have enough money fore equpemnt. To be safe, I would say that the majority of people do follow the guidelines although they may manipulate it to fit their best interest.