Problema Solution
Carla invested $23,000, part at 16% and part at 15%. If the total interest at the end of the year is $3,500, how much did she invest at 16%?
Answer provided by our tutors
Let part invested at 16% be x.
So automatically that invested at 15% is 23000-x
Simple Interest = PRT/100 where P = amount invested r = RATE T = time = 1 year for this problem
SI on 16%
SI = 16x/100
For 15%
SI = 15(23000-x)/100
Total = 3500
16x/100 + 15(23000-x)/100 = 3500
Multiply by 100 throughout
16x + 345000 - 15x = 350000
x = 5000
ANS : She invested $5000 at 16%