Write the equivalent Roman numeral for the Hindu-Arabic numeral:

$55$

Write the equivalent Roman numeral for the Hindu-Arabic numeral:

$64$

Write the equivalent Roman numerals for the following Hindu-Arabic numerals:

 $81$

Write the equivalent Roman numeral for the Hindu-Arabic numeral:

 $93$

Write the equivalent Roman numeral for the Hindu-Arabic numeral:

 $97$

Write the equivalent Roman numeral for the Hindu-Arabic numeral:

 $326$

Write the equivalent Roman numeral for the Hindu-Arabic numeral:

 $548$

Write the equivalent Roman numeral for the Hindu-Arabic numeral:

$991$

Write the equivalent Roman numeral for the Hindu-Arabic numeral:

 $1,207$