the height of a documnet on your computer screen is 20.4 cm when you change the zoom settings on your screen from 100% to 25% new image every document is a dilation of previous image of a scale factor of 0.25 what is the height of the new image

Isabelle is mixing red and blue paint to make purple paint she adds 3/10 of a fluid ounce of red to 12/25 of a fluid ounce of blue to make 1 1/30 fluid ounces of purple how many fluid ounces of red paint ounces of red paint will she need to make 3 fluid ounces of purple paint