This is to ensure that the quantity of each process is available at the same time, so that there will be no problems, otherwise workers sometimes have no problems in processing parts.

Then in order to make each program have the same throughput per hour, it should be a multiple of the least common multiple. The ratio of people should be 30/3: 30/10: 30/5 =10: 3: 6. Divide the workers into 10+3+6= 19, and then it will be simple.