Question

I need to find the expression for the nth term

Answer 1

2. 30, 24, 34, 28,
Pattern: Subtract 6, Add 10

3. 19, 18.75, 18.5, 18.25
Pattern: Subtract .25

4. 42, 56, 72, 90
This pattern is hard to explain...
1st number: 1 x 2 (2)
2nd number: 2 x 3 (6)
3rd number: 3 x 4 (12)
And so on.