A bank loaned out $25,000, part of it at the rate of 13% annual interest, and the rest at 7% annual interest. The total interest earned for both loans was $2,320.00. How much was loaned at each rate?

Answer 1

2320/25000 = 232/2500 = 58/625= 9.28%

13 - 9.28 = 3.72

9.28 - 7 = 2.28

372/228 = 93/57 = 31/19 means 31/19 as much 7% as 13%

x/y= 31/19 = x/(25000 -x) cross multiply

19x = 31(25000) - 31x

50x = 775000

x = 775000/50= 77500/5= 15500 = amount of 7%

25000- 15500 = 9500 = amount of 13%

to get 25000 of 9.28%

more conventional method

2320 = .7x + .13(25000-x)

.13x -.07x = 13(25000) - 2320

.06x = 3250 -2320 = 930

x = 930/.06 = 93000/6 = 31000/2 = 15500 = amount of 7%

25000-x = 9500 = amount at 13%