① 2430 and 1686

2430÷ 1686= 1……744

1686÷744=2…… 198

744÷ 198=3…… 150

198÷ 150= 1……48

150÷48=3……6

So the greatest common factor of 2430 and 1686 is 6.

②354 and 3009

3009÷354=8…… 177

354÷ 177=2

So the greatest common factor of 354 and 3009 is 177.

2. It takes three processes to process a machine part. In the first process, each worker can complete 8 pieces per hour, in the second process, each worker can complete 12 pieces per hour, and in the third process, each worker can complete 9 pieces per hour. How many people should be assigned to each of the three processes in order to achieve balanced production?

8. The least common multiple of12 and 9 is 72.

Top 72/8=9 people

The second road 72/ 12=6 people.

72/9= 8 people on the third road.