jim writes down numbers 1 100 ben puts red spot all even numbers and

jim writes down the numbers from 1 to 100. ben puts a red spot on all the even numbers and heen puts a blue spot on all the multiples of 3. what is the largest number that has a both red and a blue spot? how many numbers have neither a blue or a red spot? sophie puts a green spot on all the multiples of 5. how many numbers have exactly two coloured spots on them?