The first multiple of 7 that is greater than 100, is 105. (70+35 = 105).
The one before that is 98, and that's less than 100.
This is the most reliable way to solve the question (listing).
Another is to subtract 100 from 150 and divide that by 7 but that does not always work well. In this case, it does since 50 divided by 7 is 7.