A veces me cuesta dividir cuando el resultado tiene un decimal.

Yes. A veces means sometimes or at times.

• A
  • veces is a fixed expression.
• Literally, it relates to at times, but in natural English it is usually sometimes.

Examples:

• A veces estudio por la mañana. = Sometimes I study in the morning.
• A veces llueve en abril. = Sometimes it rains in April.

Because costar is often used in Spanish in a structure similar to gustar.

In me cuesta dividir:

• me = to me / for me
• cuesta = is difficult / costs effort
• dividir = to divide

So the idea is not literally I difficulty divide, but more like:

• Dividing is difficult for me
• It’s hard for me to divide

This pattern is very common:

• Me cuesta entenderlo. = It’s hard for me to understand it.
• Le cuesta madrugar. = It’s hard for him/her to get up early.

You could say Es difícil para mí, but me cuesta sounds very natural when talking about something that takes effort.

Because the subject of costar here is not I. The thing that is difficult is dividir.

So grammatically:

• dividir is the subject
• cuesta is third person singular
• me shows who experiences the difficulty

Think of it like this:

• Dividir me cuesta
• More natural Spanish word order: Me cuesta dividir

That is why it is cuesta, not cuesto.

Me is an indirect object pronoun meaning to me.

In this sentence:

• Me cuesta dividir = Dividing is hard for me

Other forms:

• Te cuesta = it’s hard for you
• Le cuesta = it’s hard for him/her/you (formal)
• Nos cuesta = it’s hard for us
• Os cuesta = it’s hard for you all (Spain)
• Les cuesta = it’s hard for them/you all

So me does not mean myself here. It means to me / for me.

Because after costar, Spanish often uses an infinitive to say what action is difficult.

Structure:

• [pronoun] + costar + infinitive

Examples:

• Me cuesta dormir. = It’s hard for me to sleep.
• Nos cuesta hablar en público. = It’s hard for us to speak in public.
• Le cuesta concentrarse. = It’s hard for him/her to concentrate.

So dividir stays in the infinitive because it names the action: to divide.

It can feel like either, depending on context. In this sentence, cuando is introducing a general situation:

• when the result has a decimal
• or more naturally in English: when/whenever the result includes a decimal

Because the sentence begins with A veces, the overall meaning is general, not about one single moment. So in practice, English speakers may understand it as:

• Sometimes I find division difficult when the answer has a decimal.
• Sometimes I find division difficult whenever the answer has a decimal.

Yes, it is natural Spanish.

• el resultado = the result / answer
• tiene un decimal = has a decimal

In maths, decimal can refer to a decimal number or a decimal place/value in context. So the sentence means the result is not a whole number and includes a decimal part.

Depending on context, Spanish speakers might also say things like:

• tiene decimales = has decimal places
• es un número decimal = it is a decimal number

But tiene un decimal is understandable and natural in everyday speech.

No. Here it is un decimal because decimal is being used as a masculine noun.

• el decimal
• un decimal

Even though adjectives ending in -al can describe masculine or feminine nouns, when decimal is used here as a noun meaning a decimal / decimal number / decimal place in context, it is masculine.

So:

• un decimal = correct
• una decimal = not correct in this sentence

Because the noun is resultado, which means result or answer.

• resultado is a masculine noun
• so it takes el

Examples:

• El resultado es correcto. = The result is correct.
• No entiendo el resultado. = I don’t understand the result.

The word resulta is not a noun here; it is a verb form from resultar.

Yes, it is in the present tense:

• cuesta
• tiene

Spanish often uses the present tense to talk about:

• general truths
• habits
• repeated situations

So the sentence means this is something that happens from time to time in general, not just right now.

That matches A veces very well:

• A veces me cuesta... = Sometimes I find it difficult...

Yes, absolutely. That sounds natural too.

Comparison:

• me cuesta dividir = I find dividing hard
• me cuesta hacer divisiones = I find doing divisions hard

The original sentence is a bit more direct and compact. Your version is slightly more explicit. Both work.

Other natural alternatives:

• A veces me resulta difícil dividir cuando el resultado tiene un decimal.
• A veces me cuesta hacer una división cuando el resultado tiene decimales.

One useful cultural/language note is about decimals in writing.

In Spain, decimals are often written with a comma, not a point:

• 3,5 instead of 3.5

But when speaking, decimal is still the normal word involved in this kind of sentence.

So if someone in Spain is talking about a result with a decimal, they may write it differently from English, even though the sentence structure is the same idea.

Yes, but the original order is the most natural.

Original:

• A veces me cuesta dividir cuando el resultado tiene un decimal.

Possible variations:

• Me cuesta dividir a veces cuando el resultado tiene un decimal.
• Cuando el resultado tiene un decimal, a veces me cuesta dividir.

These are grammatically possible, but the original sounds the smoothest and most neutral for everyday use.

Putting A veces first is very common because it sets the scene immediately: sometimes.