Problema Solution
Don Antonio invested part of 30000 pesos at 5% interest and the remaining amount at 6% interest at BPI.If his investment yields an annual income of 1620 pesos, how much did he invest at 6%?
Answer provided by our tutors
P = 30,000 pesos
r1 = 0.05 or 5% annual interest
r2 = 0.06 or 6% annual interest
I = 1,620 pesos
x = the money invested at 5%
y = the money invested at 6%
x + y = P
r1x + r2y = I
If we plug the given values we have:
x + y = 30000
0.05x + 0.06y = 1620
........
click here to see the system of equations solved for x and y
........
x = 18,000 pesos
y = 12,000 pesos
Don Antonio invested 12,000 pesos at 6%.