Final answer:
To find the first negative term in the sequence, we need to look for a pattern in the differences between the terms and continue the pattern.
Step-by-step explanation:
In this sequence, the numbers are decreasing. To determine which term is the first to be negative, we need to continue the pattern and find when the numbers will become negative. Let's look for a pattern in the differences between the terms.
The difference between the first and second terms is 400 - 390 = 10.
The difference between the second and third terms is 390 - 375 = 15.
The difference between the third and fourth terms is 375 - 355 = 20.
As we can see, the differences between the terms are increasing by 5 each time. So, the difference between the fourth and fifth term would be 20 + 5 = 25. If we subtract 25 from 355, we get 330, which is negative. Therefore, the first term to be negative is the fifth term in the sequence.