गोली और सिरप की खुराक सही है।

Here गोली means pill or tablet.

That word can also mean bullet, but the context makes the meaning clear:

• सिरप = syrup
• खुराक = dose/dosage

So in a medical sentence like this, गोली is definitely tablet/pill, not bullet.

खुराक means dose, dosage, or the amount to be taken.

In medical contexts, it often refers to:

• how much medicine should be taken
• the prescribed dose
• the proper dosage amount

So गोली और सिरप की खुराक means something like the dosage of the tablet and syrup or the dose for the tablet and syrup.

की is the genitive postposition here, meaning of or showing an association like English ’s.

Hindi uses:

• का
• की
• के

depending on the gender and number of the noun that comes after them, not the noun before them.

Here the main noun is खुराक, which is feminine singular, so the correct form is की:

• गोली और सिरप की खुराक

If the following noun were masculine singular, you would usually see का instead.

It applies to गोली और सिरप together.

So the structure is:

• गोली और सिरप = tablet and syrup
• की खुराक = dosage of

Together:

• गोली और सिरप की खुराक = the dosage of the tablet and syrup

This is normal in Hindi: the postposition comes after the whole noun phrase, not after each noun separately.

Because the sentence is talking about dosage as one overall thing, not necessarily two separate counted doses.

So गोली और सिरप की खुराक means something like:

• the dosage for the tablet and syrup
• the prescribed dosing of the tablet and syrup

If you wanted to stress separate doses for each medicine, you could use a plural idea, for example:

• गोली और सिरप की खुराकें सही हैं। = The doses of the tablet and syrup are correct.

But the singular खुराक is very natural when talking about dosage in a general or collective way.

Because the grammatical subject here is खुराक, and खुराक is singular.

Even though गोली and सिरप are two items, they are inside a modifying phrase:

• गोली और सिरप की = of the tablet and syrup

The main noun being described is:

• खुराक = dosage

So the sentence is literally structured like:

• [The dosage of the tablet and syrup] is correct.

Since खुराक is singular, the verb is singular:

• है

In this sentence, सही stays the same because it is an adjective that normally does not change form here.

So you can have:

• खुराक सही है।
• दवाइयाँ सही हैं।
• योजना सही है।

In all of these, सही remains सही.

The agreement you notice more clearly in this sentence is in the verb:

• है for singular
• हैं for plural

Hindi does not have articles like English a, an, and the.

So a noun like खुराक can mean:

• a dose
• the dose
• dosage

The exact meaning depends on context.

That is why गोली और सिरप की खुराक सही है। can naturally be translated as:

• The dosage of the tablet and syrup is correct. or
• The dose of the tablet and syrup is correct.

Yes, but it changes the structure slightly.

Compare:

• गोली और सिरप की खुराक सही है। = The dosage of the tablet and syrup is correct.

Here सही is a predicate adjective: you are saying something about the dosage.

But:

• गोली और सिरप की सही खुराक = the correct dosage of the tablet and syrup

Here सही directly modifies खुराक inside the noun phrase.

So both patterns are possible, but the original sentence is the natural way to say The dosage is correct.

The original word order is the most natural and standard:

• गोली और सिरप की खुराक सही है।

Hindi word order is somewhat flexible, but not every rearrangement sounds equally natural. In a simple statement like this, the usual pattern is:

• noun phrase + adjective/complement + है

So learners should treat the original sentence as the best default pattern.