Khan Academy has a great series of video tutorials on how to divide decimal numbers with whole numbers here:

https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-arithmetic-operations/cc-6th-dividing-decimals/v/dividing-a-decimal-by-a-whole-number

https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-arithmetic-operations/cc-6th-dividing-decimals/v/dividing-a-decimal-by-a-whole-number