Jessie needs 1 5/8 gallons of paint to paint her room. she only has 5/6 gallons of paint. how many more gallons of paint does she need?

Jessie needs 15/24 more gallons of paint.

Words such as more than us know that this problem is subtraction, info from this problem also lets us know that we need to subtract 15/8 - 5/6
To intrept this expression:

15/8 - 5/6

45/24 - 20/24

15/24

You make the fractions, with like denominators, then subtract only the numerators.

Hope this helps!