Answer:
einundzwanzig : fünfundfünfzig <----- I assumed you wanted it in German because it's in the German category
Step-by-step explanation:
21 = Twenty one = einundzwanzig <------- one (ein) and twenty (zwanzig)
55 = Fifty five = fünfundfünfzig <------- five (fünf) and fifty (fünfzig)
Hope this helps! :)