Question

wells fargo bank loaned 30,000, some at an annual rate of 7% and some at an annual rate of 3%, if the income of these loans was 1,380 how much was loaned at 7% and how much was loaned at 3%?

Answer 1

You need to set up two equations:

Let x=loaned at 7%
Let y=loaned at 3%

x+y=30,000
0.07x+0.03y=1380

Let x=30,000-y and substitute:

0.07(30,000-y)+0.03y=1380
2100-0.07y+0.03y=1380
2100-0.04y=1380
2100-1380=0.04y rearranging this you get:

0.04y=2100-1380
0.04y=720
y=18,000 substituting this into one of the equations:

x+y=30,000
x+18,000=30,000
x=30,000-18,000
x=12,000

Therefore, 12,000 was loaned at 7% and 18,000 was loaned at3%