Answer:
6, 9, 12, 15, 18
Step-by-step explanation:
Finding multiples is simple, count by 3 for as many times as you can and there are your multiples.
You could write 42/20 for #60.
6 workers-9 jobs in 3 days
In one day 6 workers can do 3 jobs
In one day 1 worker can do 0.5 job
4 workers can so 2 jobs in a day
So. They can do 10 jobs in 5 days
#13: b
#14: c
#16: c
It is very easy, have a nice day :)