You are adding 40 every time.
The 100th term is 7+(99*40)=3967
Answer:
10
Step-by-step explanation:
10. ................ ..........
The answer is 2 in 20 or 1 in 10, all you have to do is add up the total number of marbles and then have the number of yellow in the total. So 2 in 20. Hope this helps you!

Answer : He spends 2 hours doing paperwork each day.
Hope this helps. - M