Es inútil comparar tu progreso con el de otras compañeras; cada una aprende a su ritmo.

Both word orders are possible in Spanish:

• Es inútil comparar tu progreso...
• Comparar tu progreso... es inútil

The version in your sentence is very natural and common. It uses an impersonal structure: Es + adjective + infinitive.

This pattern is extremely frequent in Spanish:

• Es importante estudiar.
• Es difícil entenderlo.
• Es mejor esperar.

So Es inútil comparar... means It’s useless to compare...

Because after Es inútil, Spanish normally uses an infinitive to talk about an action in a general way.

So:

• Es inútil comparar = It’s useless to compare
• not Es inútil comparas
• not Es inútil compare

The infinitive comparar works a bit like the English to compare or comparing in this kind of sentence.

Because Spanish does not use de after inútil in this structure.

The pattern is:

• Es inútil + infinitive
• Es difícil + infinitive
• Es importante + infinitive

Examples:

• Es inútil discutir.
• Es difícil aprender eso.
• Es importante practicar cada día.

So Es inútil comparar is correct, while Es inútil de comparar is not natural Spanish here.

Here inútil means useless, pointless, or not helpful.

So the sentence is not saying that comparing is impossible. It is saying that doing so is not useful.

Similar examples:

• Es inútil preocuparse tanto. = It’s useless to worry so much.
• Fue inútil intentarlo. = It was pointless/useless to try.

El de replaces a repeated noun phrase.

Full version:

• comparar tu progreso con el progreso de otras compañeras

To avoid repeating progreso, Spanish says:

• comparar tu progreso con el de otras compañeras

Here el stands for el progreso, and de otras compañeras means of other classmates / of other female classmates.

So:

• el de otras compañeras = the one of other classmates, more naturally in English, that of other classmates

This is a very common Spanish structure:

• Mi coche es más rápido que el de Juan. = My car is faster than Juan’s.
• Tu idea es mejor que la de Ana. = Your idea is better than Ana’s.

Yes, absolutely. That version is grammatically correct.

• comparar tu progreso con el progreso de otras compañeras
• comparar tu progreso con el de otras compañeras

The second version is more natural because it avoids repetition. Spanish often prefers this kind of shorthand.

Because compañeras is the feminine plural form of compañero/a.

This suggests that the sentence is talking about other female classmates/colleagues. Maybe the person being addressed is a woman in a group of women, or the context is specifically female.

Forms:

• compañero = male classmate/colleague
• compañera = female classmate/colleague
• compañeros = male or mixed group
• compañeras = female group

So if the group were mixed or unspecified, Spanish often uses:

• otras compañeras y compañeros
• or simply otros compañeros in more traditional generic usage

But in your sentence, the feminine is chosen on purpose.

Not always. Compañera can mean different things depending on context:

• classmate
• colleague
• teammate
• sometimes more generally companion

In a learning/progress context like this, classmates is probably the most natural interpretation.

In Spain, compañero/a is very common and flexible.

Because cada una refers back to otras compañeras, which is feminine.

• cada una = each one / each woman
• cada uno = each one / each man, or masculine default in some contexts

Since the sentence is about compañeras, the feminine form matches:

• otras compañeras; cada una aprende...

If it were about compañeros, you would expect:

• otros compañeros; cada uno aprende...

Because cada una is grammatically singular.

Even though it refers to multiple individuals one by one, Spanish treats cada + singular noun/pronoun as singular:

• Cada una aprende...
• Cada estudiante tiene...
• Cada persona necesita...

So:

• cada una aprende = each one learns

Not:

• cada una aprenden

Literally, a su ritmo means at her own pace or at their own pace depending on context.

The preposition a is part of the fixed expression:

• ir a buen ritmo = to go at a good pace
• trabajar a otro ritmo = to work at another pace
• aprender a su ritmo = to learn at one’s own pace

So you should learn a + ritmo as a natural pattern.

Because the sentence talks about each person individually:

• cada una aprende a su ritmo = each one learns at her own pace

For each individual person, there is one ritmo. So singular su ritmo is the natural choice.

If you said sus ritmos, that would sound like each person has multiple paces, which is not the intended meaning.

Also remember that su can mean:

• his
• her
• its
• your (formal)
• their

Here it means something like her own for each individual person.

Because Spanish normally expresses one’s own pace as:

• a su ritmo

This is the standard, idiomatic phrasing.

Forms like al ritmo suyo sound unnatural here. Spanish generally prefers the possessive adjective before the noun:

• su ritmo rather than a heavier form like
• el ritmo suyo

The latter can exist in some contexts for emphasis, but not as the normal way to say at their own pace.

The semicolon links two closely related complete ideas:

• Es inútil comparar tu progreso con el de otras compañeras
• cada una aprende a su ritmo

The second clause explains or supports the first one.

You could also write this as:

• Es inútil comparar tu progreso con el de otras compañeras, porque cada una aprende a su ritmo.
• Es inútil comparar tu progreso con el de otras compañeras. Cada una aprende a su ritmo.

The semicolon is a stylistic choice that sounds a bit polished and clear.

Yes, but it would change the nuance.

• otras compañeras = other classmates in general
• las otras compañeras = the other classmates, a more specific group already known in context

In your sentence, otras compañeras is more general and works well because the statement is broad and advice-like.

Because progreso here refers to your overall progress as a single concept.

• tu progreso = your progress

Spanish often uses the singular for abstract ideas like this:

• tu progreso
• tu nivel
• tu experiencia

You might hear tus progresos in some contexts, but it sounds more like the improvements you’ve made or your advances, not the general idea of progress.

Yes, comparar can be used with con very naturally.

Two common patterns are:

• comparar X con Y
• comparar X y Y

So both are possible:

• Comparó su trabajo con el mío.
• Comparó su trabajo y el mío.

In your sentence, comparar tu progreso con el de otras compañeras is completely standard and very natural.

It is mostly general Spanish and would be understood anywhere.

Nothing in it is strongly Spain-only. However, it fits Spain very naturally too.

A few notes:

• compañeras is common in Spain and elsewhere.
• The punctuation and grammar are standard.
• The wording sounds natural in both European and Latin American Spanish.

So a learner of Spanish from Spain can safely learn it as a normal sentence.