Questions & Answers about Голоса инспекторов были тихие.
Why does the masculine noun голос end in -а in this sentence?
Голоса is the nominative plural of голос (voice). While most masculine nouns take -ы or -и in the plural, a specific group takes a stressed -а or -я. This is exactly the pattern your current lesson covers!
Since голоса ends in -а, shouldn't the adjective ending look feminine?
No, because grammatical gender is determined by the singular form of the noun. Голос is masculine. Even though its plural голоса looks like a feminine singular noun, it is still grammatically plural, so it requires the plural adjective ending -ие seen in тихие.
Why is инспекторов used here instead of a nominative plural form?
It is in the genitive plural because it means 'of the inspectors', showing possession over the voices. Notice that even though инспектор can also take a stressed -а in the nominative plural (инспектора), its genitive plural still uses the standard masculine -ов ending.
Why is the adjective тихие used here instead of the adverb тихо?