Interest rate per year = 6% or 0.06
Interest rate per month = 0.06 ÷ 12 = 0.005
Amount in savings account for first six months = 15,000
Amount in savings account for next six months
= 15,000 + 20,000
= 35,000
Interest that will be earned at the end of the year
= (15,000 × 0.005 x 6) + [ (20,000+15,000) × 0.005 x 6]
= (15,000 × 0.03) + (35,000 ×0.03)
= (450) + (1,050)
= 1,500
The account will earn Php 1,500 interest at the end of the year.