# math

posted by
**partha**
.

If the common difference of an A.P. is 7, then what is a20-a11?

?

1) 64

2) 65

3) 66

4) 63

posted by
**partha**
.

If the common difference of an A.P. is 7, then what is a20-a11?

?

1) 64

2) 65

3) 66

4) 63