Which of the following is a grammatically acceptable sentence?

Concept

When a number and a unit (here, a currency denomination) combine to form an attributive modifier before a noun, the number and the unit both stay singular; only the head noun that is actually being counted takes the plural marker — the same pattern as "a ten-page report" becoming "several ten-page reports", never "tens-pages report".

Application

In "Give me four ___ notes," the modifier is "five rupee" (a number plus a currency unit) placed before the head noun "notes." By the rule above, "five" and "rupee" inside that modifier must both stay singular, while the head noun "notes" must be pluralized because the quantity "four" is more than one:

• "Four fives rupees notes" wrongly pluralizes both "five" and "rupee" inside the modifier.

• "Four five rupee note" leaves the head noun "note" singular despite the quantity "four."

• "Four five rupees notes" wrongly pluralizes "rupee" inside the modifier, even though "notes" is correctly pluralized.

• Only "Give me four five rupee notes" keeps the modifier singular and pluralizes solely the head noun, satisfying both parts of the rule.

Cross-check

This mirrors the familiar pattern "a five-year plan" becoming "four five-year plans" — the number + unit modifier stays singular and only the head noun pluralizes, confirming the same structure holds here.