State the nth term of the following sequence: 3, 7, 11, 15, 19

First we look at the jump between each term:7-3=4, 11-7=4, 15-11=4, 19-15=4So we know that the difference in each step is 4. So our expression with look like 4n+d for some number d.Comparing what we have with what we want:4+d, 8+d, 12+d, 16+d, 20+d 3 7 11 15 19So d=-1. Hence the nth term expression is 4n-1.