Rate/interest word problem

Question

A man invested $5,000 partly at 4% and partly at 6%, so that he earned $275 total interest. What amount did he invest at each rate?

Answer 1

Daniella, I would invest in some tutoring or go see your teacher.

 

a + b = 5000 ------> a = 5000 - b

.04a + .06b = 275

 

.04(5000 - b) + .06b = 275

200 - .04b + .06b = 275

.02b = 75

b = 3750

 

a = 5000 - 3750 = 1250

 

Hope this helps.