Sula's grandmother visits every fifth month. her grandfather visits every sixth month. the ladt time they both visited in the same month was january, 1995 when will they next both visit in the same month?

The best thing to do here is to list the multiples as such, or each time her grandmother comes, and each time her grandfather comes, and see when they come together.
Grandmother- 01/95, 06/95, 11/95, 4/96, 9/96, 02/97, 07/97, 12/97, 05/98, 10/98, 3/99, 8/99, 1/00, 6/00, 11/00, 4/01, 9/01, 02/02, 07/02, 12/02

Grandfather- 01/95, 07/95, 01/96, 07/96, 01/97, 07/97, 01/98, 07/98

From this, you can see that they both visit again on 07/97, which is July of 1997.
Hope this has been able to help you :)