Answer:
let the size of the real item be x
then the size of model as prodived will be =
60% of X
60/100 × X
=3X/5 .
That's of course the 30/60/90 right triangle.
If you need to see the algebra, the acute angles in a right triangle are complementary, adding to 90 degrees:
x + 2x = 90
3x = 90
x = 30
The correct answer is the letter B