A stitch in time saves nine. A penny saved is a penny earned. These sentences are ... similar in meaning opposite in meaning neither the same nor the opposite

Neither the same nor the opposite

Explanation:

A stitch in time saves nine is an idiom meaning that it's better to deal with problems right away and spend less time doing that than later when more time is going to be needed.

A penny saved is a penny earned is an idiom meanings that saving money, even little by little, is as useful as earning more.

When we compare these two idioms, we can see that their meanings are neither the same nor the opposite.