Conditional Formatting Formula for Duration

Question

Start Duration  1  2  3  4  5  7  8  9  10  ...
1     5
4     5
4     8
10    8
10    2
15    22

Is there a formula I can use similar to something like this? =AND(C$1>=$A2, C$1<=B2)
It's like a gantt chart

Answer 1

Use this:

=AND(C$1>=$A1,C$1<=$A1+$B1-1)