Since 10 percent of 45 is 4.50, 5 percent of 45 will be half that amount, or 2.25, and 15 percent will be the sum of those two figures, or 6.75 (4.50 + 2.25 = 6.75).
10 protsenti 210 - st on 21, järelikult 5 protsenti 210 - st on 21 - st pool ehk 10,5. 15 protsenti on nende kahe arvu summa ehk 31,5 (21 + 10,5 = 31,5).