Multiples of 15 are: 15,30,45,60,75,90,105,120,135,150,165,180,195,210,225,240,255,270,285,300,315,330,345,360,375,390,405,420,435,450,465,480,495,510,525,540,555,570,585,600,615,630,645,660,675,690,705,720,735,
You would have to transform the fractions to decimals by dividing. For the first one, if you divide 4 by 5 you get .8. To transform a decimal to percent you move the decimal place 2 times to the right or multiply by 100 (They both would give you the same thing)