 
 <translate> First find Charlie's floor number by dividing Frank's floor number by 4: 16 / 4 = 4. Then add 2 to find Dennis' floor number: 4 + 2 = 6.
Thus, the answer is 6. <hau> Na farko sami lambar bene na Charlie ta hanyar raba lambar bene na Frank ta 4: 16 / 4 = 4. Sai ka ƙara 2 don ka sami lambar bene na Dennis: 4 + 2 = 6. Saboda haka, amsar ita ce 6. 